Which one of the following most accurately describes the author's purpose in the last paragraph of the passage?

Shiyi on February 2 at 09:59PM

Why is A incorrect?

Why is A incorrect?

1 Reply

Ravi on February 8 at 08:15PM

@Shiyi-Zhang,

Happy to help.

The question asks, "Which one of the following most accurately
describes the author’s purpose in the last paragraph of the passage?"

The last paragraph gives us an implication of the new evidence
discussed earlier in the passage, saying that it provides evidence to
overturn the assumption that parasitic interactions evolve over time
to symbiosis. The researchers determined that this assumption didn't
apply to fungi, as they found fungi that are benign and harmful in the
early and late stages of fungus evolutionary history. This tells us
that the author believes that fungi can begin being benign and
symbiotic but then later on become harmful to their hosts.

We're looking for the answer choice that most closely aligns with our
summary of the last paragraph.

You asked about (A).

(A) says, "to suggest that new research overturns the assumption that
lichen-forming fungi are primarily symbiotic, rather than parasitic,
organisms."

The problem with this answer choice is that the research did not
overturn the assumption that lichen-forming fungi are primarily
symbiotic, rather than parasitic, organisms. From the information we
have, the research does not change the fact that a lichen consists of
a fungus living in symbiosis with an alga (lines 1 and 2). Rather, the
key assumption that the research discussed in the last paragraph
called into question was the assumption that parasitic interactions
always evolve toward symbiosis (this is discussed in the first 6 lines
of the final paragraph, which are lines 45 through 50). As a result,
we know that (A) is identifying the wrong assumption that the evidence
in the final paragraph overturns, so we can get rid of this answer
choice.

(B) says, "to show that findings based on new research regarding
fungus classification have implications that affect a long-standing
assumption of evolutionary science."

(B) matches up really well with our summary of the final paragraph,
which is above. We know that the last paragraph deals with discussing
the implications of the research into the DNA of the lichen-forming
fungi discussed in the passage. We also know that the research is
challenging the assumption that all parasitic interactions always
evolve toward a symbiotic relationship (this is discussed in lines 45
through 50). Since this answer choice discusses the implications of
research that affect a long-standing assumption of evolutionary
science, we know it's the correct answer choice.

Does this help? Let us know if you have any more questions!