Correct Answer: A

Rationale: The correct answer is A. Structured interviews do not yield the same depth of information as a clinical interview because they involve a set of standardized questions that are asked in the same way to all participants. This lack of flexibility may limit the depth and richness of the responses obtained compared to a more open-ended clinical interview. Choices B, C, and D are incorrect because structured interviews are not flexible in question phrasing, do not necessarily bring together a wide range of information on one person, and can provide insights into participants' reasoning behind responses depending on the design of the structured questions.

Correct Answer: C

Rationale: Longitudinal research involves tracking the performance of each person over time. By doing so, researchers can observe common patterns in development among a group of individuals and also identify individual differences in how each person progresses over time. This methodology allows researchers to gather data on the same individuals repeatedly, offering insights into how development unfolds over the lifespan. Choices A, B, and D are incorrect because longitudinal research focuses on observing individuals over time rather than studying groups at a single point, randomly assigning participants to treatments, or conducting quasi-experiments.

Correct Answer: D

Rationale: At around 4 months of age, babies begin to develop a preference for salty taste over plain water. This preference is part of their sensory development and exploration of tastes. Introducing a variety of flavors, including salty tastes, at this stage helps broaden the baby's palate and acceptance of different foods later on. Choices A, B, and C are incorrect as babies typically do not develop a preference for salty tastes over plain water at 2 weeks, 6 weeks, or 2 months of age. These earlier stages are more focused on milk feeding and the introduction of solid foods usually begins around 4-6 months of age.

Correct Answer: D

Rationale: If pregnancy does not occur, the corpus luteum will shrink. As a result, the lining of the uterus is discarded through the process of menstruation. This shedding of the uterine lining is what causes menstrual bleeding. Choices A, B, and C are incorrect because they do not describe the physiological response of the body when pregnancy does not occur. The corpus luteum shrinking and the subsequent shedding of the uterine lining are part of the menstrual cycle, not processes related to cell duplication, zygote multiplication, or the duration of the germinal period.

Correct Answer: C

Rationale: During the second trimester of pregnancy, a white, cheeselike substance called vernix emerges on the skin of the developing fetus. Vernix is a protective layer that helps prevent the skin from becoming waterlogged during the time in the amniotic fluid. Choice A, lanugo, is incorrect as lanugo refers to the fine, soft hair that covers the body of a fetus. Choice B, corpus luteum, is incorrect as it is a temporary endocrine structure involved in the menstrual cycle. Choice D, chorion, is incorrect as it is one of the membranes that surround the embryo and later the fetus.