What is the best-known effect of smoking during the prenatal period?

Correct Answer: C

Rationale: The best-known effect of smoking during the prenatal period is low birth weight. Smoking during pregnancy is a known teratogen that can lead to negative outcomes for the developing fetus, such as growth restrictions resulting in low birth weight. This condition can have significant long-term consequences on the child's health and development. Choices A, B, and D are incorrect as they are not the primary effect associated with smoking during the prenatal period. Colic is typically associated with digestive issues, respiratory distress at birth can be caused by various factors other than smoking, and delayed language development is not directly linked to smoking during pregnancy.

Correct Answer: C

Rationale: According to psychosexual theory, developed by Sigmund Freud, how parents manage their child's sexual and aggressive drives in the first few years is crucial for healthy personality development. This theory suggests that personality development is heavily influenced by a child's experiences during early stages of development, particularly related to handling sexual and aggressive impulses. Choices A, B, and D are incorrect as they do not align with the core principles of psychosexual theory, which focuses on the importance of early childhood experiences, especially in the context of sexual and aggressive drives.

Correct Answer: D

Rationale: The information-processing approach views the human mind as a symbol-manipulating system through which information flows. This perspective emphasizes how information is received, processed, stored, and retrieved in the mind, similar to how a computer processes data through symbols and operations. Choices A, B, and C are incorrect because they do not align with the fundamental principles of the information-processing approach, which focuses on the mind's symbolic manipulation of information rather than being a socially mediated process, a collection of stimuli and responses, or a system of genetically programmed behaviors.

Correct Answer: B

Rationale: Arnold Gesell is generally regarded as the founder of the child study movement, emphasizing the importance of observing and documenting children's behaviors to understand their development. While he was a significant figure in child development research, he did not specifically write child-rearing books for parents, foreshadow lifespan research, or construct the first successful intelligence test. Choice A is incorrect as Gesell's focus was more on research rather than writing child-rearing books. Choice C is incorrect as Gesell's main contributions were in child development, not specifically in aging research. Choice D is incorrect as Gesell is not credited with constructing the first successful intelligence test.

Correct Answer: C

Rationale: The germinal period lasts about two weeks and occurs during the first two weeks of pregnancy. This is the time when the fertilized egg implants into the uterus and begins to divide rapidly. It is followed by the embryonic period, which lasts from about week 3 to week 8 of pregnancy. Choice A is incorrect because the germinal period happens in the early stages of pregnancy, not the second trimester. Choice B is incorrect because the germinal period typically lasts about two weeks, not six. Choice D is incorrect because the germinal period is an early stage of pregnancy and not the final period of a 38-week pregnancy.

Correct Answer: C

Rationale: According to research, mothers who are supported by a trained companion during childbirth have fewer birth complications and shorter labors. This support can reduce stress and anxiety levels, provide comfort and encouragement, and help the mother feel more in control during labor and delivery. Overall, having a trained companion present can contribute to a more positive childbirth experience for the mother. Choices A, B, and D are incorrect because they do not align with the research findings that specifically highlight the benefits of having a trained companion during childbirth.

Correct Answer: A

Rationale: Theorists who emphasize plasticity believe that change in response to influential experiences is possible. They argue that individuals have the capacity to adapt and change their behavior based on their experiences, rather than being limited by genetic predispositions or early childhood experiences. This perspective highlights the importance of environmental influences in shaping behavior and development. Choices B, C, and D are incorrect because they do not align with the concept of plasticity, which emphasizes the flexibility and adaptability of individuals in response to their experiences, rather than being fixed by heredity, childhood traits, or early experiences.

Correct Answer: D

Rationale: Cross-sectional studies can be threatened by cohort effects because different age groups may have experienced different historical or social contexts, influencing the results. This disparity can lead to invalid comparisons between age groups, confounding the study's findings. Option A, practice effects, refer to changes in participants' behavior due to repeated testing, not a specific threat to cross-sectional studies. Participant dropout (Option B) is a threat related to attrition in longitudinal studies, not cross-sectional studies. Sequential timing (Option C) does not pose a threat to cross-sectional studies; instead, it refers to the order of tasks in a study design.

Correct Answer: B

Rationale: Baby Ian is demonstrating the Moro reflex. The Moro reflex is a normal newborn reflex that occurs when a baby feels like they are falling or losing support. It is characterized by arching the back, extending the legs, throwing the arms outward, and then bringing the arms in toward the body. This reflex is a primitive survival instinct that typically disappears around 6 months of age. Choice A, palmar grasp, involves the baby's fingers closing around an object when it touches their palm. Choice C, tonic neck reflex, involves the baby assuming a fencing position when their head is turned to one side. Choice D, Babinski reflex, is characterized by the fanning out and curling of the baby's toes when the sole of the foot is stroked.