Correct Answer: A

Rationale: Vygotsky's emphasis on culture and social experience did not lead him to neglect the biological side of development. Instead, he believed that biological factors and social influences interact to shape cognitive development. Choice A is correct because it reflects Vygotsky's view that biological factors and social experiences work together in cognitive development. Choices B, C, and D are incorrect as Vygotsky's emphasis was not on overemphasizing heredity, focusing solely on independent efforts of children, or placing too much emphasis on children's capacity to shape their own development.

Correct Answer: D

Rationale: Sydney's approach of starting with a hypothesis, deducing testable inferences, and isolating and combining variables to confirm inferences aligns with the characteristics of the formal operational stage in Piaget's theory of cognitive development. This stage typically emerges during adolescence and is characterized by advanced logical thinking, abstract reasoning, and the ability to think systematically about all possible outcomes of a problem. Choice A, sensorimotor, is incorrect as it pertains to the stage where infants learn through sensory experiences and motor actions. Choice B, preoperational, is incorrect as it involves egocentrism and lack of conservation. Choice C, concrete operational, is incorrect as it focuses on operational thought and logical reasoning in concrete contexts.

Correct Answer: D

Rationale: The difficulty in isolating the precise damage caused by illegal drugs during pregnancy is due to the fact that drug users often take several drugs, display other high-risk behaviors, and suffer from other stresses. This makes it challenging to identify the specific impact of each individual factor on prenatal development. Choices A, B, and C are incorrect because they do not address the complexity of the situation involving drug users during pregnancy. Most drug-using mothers refusing to participate in teratology research, the majority of babies not surviving, or drug-using mothers quitting during the first trimester do not directly explain the difficulty in isolating the precise damage caused by illegal drugs during pregnancy.

Correct Answer: D

Rationale: Swaddling newborns restricts their movement by wrapping them snugly in a blanket, which helps to mimic the feeling of security they had in the womb. It also helps to maintain their warmth and can promote better sleep patterns. Choices A, B, and C are incorrect because swaddling does not increase crying, hinder early motor development, or promote an insecure attachment relationship. Instead, it provides comfort, warmth, and a sense of security for newborns.

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.