Correct Answer: B

Rationale: When examining heredity and mental disorders, it is important to note that these conditions are influenced by multiple genes working together. Mental disorders are complex traits that arise from the interplay of various genetic and environmental factors. Therefore, choice B, 'influenced by multiple genes,' is the correct answer. Choice A, 'influenced by one particular gene,' is incorrect because mental disorders typically do not result from the action of a single gene. Choice C, 'influenced by recessive genes,' is incorrect as it oversimplifies the genetic basis of mental disorders. Choice D, 'not influenced by genes,' is also incorrect as genes play a significant role in the development of mental disorders.

Correct Answer: B

Rationale: The correct answer is B: 'necessary cause.' A necessary cause must be present for a disorder to occur. In the context of developing chicken pox, being exposed to the virus is a necessary condition for contracting the disease. Choices A, C, and D are incorrect. A 'risk factor' increases the probability of developing a disease but is not essential for its occurrence. A 'sufficient cause' can produce the outcome on its own, which is not the case with exposure to the chicken pox virus. A 'contributory cause' adds to other causes to produce an effect, but in this scenario, exposure to the virus is crucial by itself.

Correct Answer: C

Rationale: Newer psychodynamic perspectives do not view the libido as a primary determinant of behavior. While Freud's theories focused heavily on the libido as a driving force, newer perspectives have evolved to consider a broader range of factors influencing behavior. Choice A is incorrect as newer perspectives still build upon some elements of Freud's theories. Choice B is incorrect as newer perspectives may not solely emphasize the role of the id. Choice D is incorrect as while intrapsychic conflicts are considered important, they are not always viewed as the sole primary determinant of behavior in newer psychodynamic perspectives.

Correct Answer: A

Rationale: The correct answer is A. Studying specific gene defects is not a common method for investigating genetic influences. Choices B, C, and D are common methods used in genetic research. Twin studies help determine the heritability of traits, adoption studies compare similarities between adopted individuals and their adoptive families versus biological families, and family history studies track the inheritance patterns of traits within families.

Correct Answer: A

Rationale: In understanding abnormal behavior, it is crucial to differentiate between necessary, sufficient, and contributory causes. Necessary causes are those that are required for a disorder to develop, meaning that without them, the disorder would not occur. However, their presence does not guarantee the occurrence of the disorder. Sufficient causes, on the other hand, are those that alone can guarantee the development of a disorder, but they are not the only factors that can lead to it. Contributory causes are factors that increase the likelihood of a disorder but are not essential on their own nor do they guarantee the disorder. Therefore, choice A is the correct answer as it accurately describes the role of necessary causes in the development of abnormal behavior. Choices B, C, and D are incorrect as they misrepresent the definitions and roles of sufficient and contributory causes in causing abnormal behavior.