Correct Answer: D

Rationale: In the eighth month of pregnancy, lanugo typically is shed. Lanugo is the fine, downy hair that covers a fetus's body to help regulate body temperature while in the womb. By the eighth month, many fetuses shed this hair as they prepare for birth. Choices A, B, and C are incorrect because fetal growth doubling, neuron production increasing, and the formation of eyes, ears, nose, jaw, and neck occur in earlier stages of pregnancy, not specifically in the eighth month.

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: A

Rationale: A major strength of the longitudinal design is that researchers can examine relationships between early and later behaviors. This design allows researchers to observe and track changes in the same participants over an extended period of time, providing valuable insights into developmental trajectories and how behaviors are connected across different stages of life. Choice B is incorrect because longitudinal studies track changes over time, not necessarily collect a large amount of data in a short time span. Choice C is incorrect as it refers to cross-sectional studies rather than longitudinal studies. Choice D is incorrect as it describes a cross-sectional design where participants of different ages are studied at the same time.

Correct Answer: A

Rationale: When the blastocyst burrows deep into the uterine lining, this process is known as implantation. Implantation is a crucial step in the early stages of pregnancy where the blastocyst attaches to the uterine wall in order to receive nourishment and continue developing. Choice B is incorrect because implantation is a necessary step for pregnancy to occur. Choice C is incorrect as implantation marks the beginning of further growth and development. Choice D is incorrect as the duplication of cells occurs during earlier stages of development, not during implantation.

Correct Answer: C

Rationale: Self-reports can range from relatively unstructured interviews to highly structured interviews, questionnaires, and tests. This variety allows researchers to collect information from participants in different ways, depending on the research goals and the type of information being sought. Choices A, B, and D are incorrect because they do not accurately describe the range and flexibility of self-reports as outlined in the field of research methodology.