The Following Questions Refer to Figure 22

question 48

Multiple Choice

The following questions refer to Figure 22.1, which shows an outcrop of sedimentary rock whose strata are labeled A-D.

Figure 22.1
-If x indicates the location of fossils of two closely related species, then fossils of their most-recent common ancestor are most likely to occur in which stratum?

• A) A
• B) B
• C) C
• D) D

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Definitions:

HIV Diagnosis

The process of testing and confirming the presence of the HIV (Human Immunodeficiency Virus) in an individual.

CD4 Count

A measure of the number of CD4+ T lymphocytes in the blood, used to assess the immune system's health in individuals, particularly those with HIV/AIDS.

Healthy Person

An individual who enjoys physical, mental, and social well-being, free from major diseases or disorders.

Opportunistic Infections

Infections that occur more frequently and are more severe in individuals with weakened immune systems, such as those with HIV/AIDS.