In an investigation of over 120,000 New York City births, babies born even 1 to 2 weeks early __________ than children who experienced a full-length prenatal period.

Correct Answer: A

Rationale: In the investigation of over 120,000 New York City births, babies born even 1 to 2 weeks early showed lower reading and math scores at a third-grade follow-up compared to children who experienced a full-length prenatal period. This suggests that being born slightly premature can have an impact on cognitive development, leading to educational challenges later on. Choices B, C, and D are incorrect because the study specifically highlighted lower reading and math scores, not a reduced likelihood of suffering from childhood obesity or neurological impairments, or improved language and social/emotional scores in early childhood.

Correct Answer: C

Rationale: During the third stage of labor, the correct answer is C, the placenta is delivered. This stage occurs after the baby is born and involves the expulsion of the placenta from the uterus. Choice A is incorrect because the thinning of the cervix to nothing typically occurs during the first stage of labor. Choice B is incorrect as uterine contractions usually begin during the first stage of labor to help with the dilation of the cervix. Choice D is incorrect because the baby is typically born in the second stage of labor, not the third.

Correct Answer: C

Rationale: In field experiments, researchers randomly assign participants to treatment conditions in natural settings. This method allows for a higher level of control over potential confounding variables compared to non-random assignment. Random assignment helps ensure that the groups being compared are comparable at the beginning of the study, which strengthens the internal validity of the research findings. Choice A is incorrect because selective assignment may introduce bias. Choice B is incorrect as researchers can use random assignment in field experiments. Choice D is incorrect because field experiments typically have less control over the treatment compared to laboratory experiments.

Correct Answer: C

Rationale: Young infants usually cry because of physical needs such as hunger, discomfort, or needing to be changed. It is their way of communicating these needs to their caregivers as they are unable to do so in any other way. Choice A is incorrect because infants cry primarily to communicate physical needs, not because they are bored. Choice B is incorrect because the tone of the cry is not the reason why infants cry. Choice D is incorrect because infants cry for various physical needs, not necessarily all night long.

Correct Answer: D

Rationale: The correct answer is D because the description of the twisting and fanning out of newborn Takeo's toes suggests the Babinski reflex, which is typically elicited by stroking the sole of the foot from toe to heel. The Babinski reflex is a normal response in newborns and indicates proper neurological development. Choices A, B, and C are incorrect as they do not elicit the specific response described in the question.

Correct Answer: D

Rationale: Taking tests and answering questionnaires are examples of research methods. Research methods refer to the specific approaches used in conducting research, such as collecting data, analyzing information, and drawing conclusions. In this case, tests and questionnaires are tools used to gather information and data for research purposes, making them examples of research methods. Choices A, B, and C are incorrect because research designs refer to the overall structure and plan of a study, theories are explanations developed through research and observation, and hypotheses are specific predictions or statements that can be tested through research.

Correct Answer: B

Rationale: The sense of smell in mammals, including humans, plays a crucial role in helping mothers and babies identify each other. This is important for initiating bonding and caregiving behaviors. Choice A is incorrect because the sense of smell is functional at birth and not entirely underdeveloped for several years. Choice C is incorrect as the sense of smell is actually well-developed at birth. Choice D is incorrect because the sense of smell is functional from birth and does not take several months to become adultlike.

Correct Answer: A

Rationale: According to Jean Piaget's cognitive-developmental theory, children actively construct knowledge as they manipulate and explore their world. Piaget emphasized that children learn through their own actions and interactions with the environment, leading to cognitive development. Choice B is incorrect because Piaget's theory focuses on children's active engagement in learning rather than passive reinforcement. Choice C is incorrect because Piaget's theory highlights the child's role in constructing knowledge, not solely relying on adult teaching. Choice D is incorrect as it refers to sensitive periods, a concept more associated with other developmental theories like Erikson's psychosocial theory, not Piaget's cognitive-developmental theory.

Correct Answer: A

Rationale: Having access to social support during stressful periods can greatly reduce the effects of stress on the developing organism. Social support can provide emotional comfort, practical assistance, and a sense of belonging, which can help the expectant mother cope with stress more effectively. This support system can also help mitigate the negative impact of stress on the developing baby during pregnancy. Choices B, C, and D are incorrect because while folic acid is important for prenatal health, it does not directly address the effects of stress. Taking anti-anxiety medication should be done under medical supervision and as a last resort due to potential risks to the developing baby. Bed rest during the last trimester is not a solution to reduce the effects of stress and may not address the underlying causes of stress.