|Question 7Verbal

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Text
Wenheng Zhang and colleagues have explored how convergent evolution-a phenomenon that occurs when the same trait evolves independently in two reproductively separate lineages-can result from a genetic mechanism shared by both lineages. Meanwhile, Patricia J. Wittkopp and colleagues have investigated how convergence occurs through different genetic mechanisms, but the relative prevalence of convergence through shared and different genetic processes is still poorly understood. This motivated biologists Delbert A. Green II and Cassandra G. Extavour to evaluate both types of convergence in a single study for their 2012 paper.
Which choice best states the function of the underlined portion in the text as a whole?
It clarifies a concept that the author implies was unclear in the studies mentioned in the text.
A
It provides examples of how a phenomenon was studied by scientists in the field before Green and Extavour's study.
B
It introduces a method of scientific analysis that is discussed in greater detail later in the text.
C
It gives a basic description of a phenomenon that is central to the discussion that follows.
D