Correct Answer: A

Rationale: The limitation of the ethnographic method is that investigators' cultural values sometimes lead them to misinterpret what they see. This can introduce bias into the observations and potentially impact the accuracy of the findings. It is important for researchers to be aware of their own biases and strive to minimize their influence when conducting ethnographic studies. Choice B is incorrect because ethnographic methods actually aim to provide rich information on how individuals behave within their cultural contexts. Choice C is incorrect as ethnographic methods typically involve direct observation and participation rather than unobtrusive techniques like surveillance cameras. Choice D is incorrect because one of the strengths of ethnographic research is its ability to uncover the reasoning behind participants' responses by immersing the researcher in the cultural setting.

Correct Answer: D

Rationale: Dr. Rizvi's approach to development, involving studying the relationship between changes in the brain and cognitive processing and behavior patterns, aligns with developmental cognitive neuroscience. This field combines research from various disciplines to understand how brain development influences cognitive processes and behaviors. Choice A, behaviorism, focuses on observable behaviors influenced by external stimuli. Choice B, cognitive-development theory, emphasizes cognitive growth stages. Choice C, the information-processing approach, centers on how individuals perceive, store, and retrieve information.

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: D

Rationale: The correct answer is D because investigators who study development aim to identify the factors that influence consistencies and transformations in people from conception to death. This goal encompasses various domains such as physical, cognitive, emotional, and social development, highlighting the comprehensive nature of developmental research. Choices A, B, and C are incorrect as they do not align with the overarching goal of developmental researchers, which is to understand the factors influencing individuals throughout their lifespan, rather than focusing solely on genetic factors, environmental factors related to disease, or abnormal development in specific age groups.

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.