The Following Questions Refer to Figure 19

question 19

Multiple Choice

The following questions refer to Figure 19.1, which shows an outcrop of sedimentary rock whose strata are labeled A-D.
Figure 19.1
-Currently, two extant elephant species (X and Y) are placed in the genus Loxodonta and a third species (Z) is placed in the genus Elephas. Assuming this classification reflects evolutionary relatedness, which of the following is the most accurate phylogenetic tree?

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Definitions:

Comparison Group

A group in a study that does not receive the experimental treatment and is used as a benchmark to measure the effect of the treatment.

Cross-Sequential Design

A research design that combines both cross-sectional and longitudinal methods to study how individuals of different ages change over time.

Surveys

Surveys are research methods that collect data from a predetermined group of respondents to gain information and insights on various subjects.

Evolutionary Theory

A scientific theory that proposes species change over time through processes like natural selection and genetic drift, explaining the diversity of life on Earth.