Australian embryologists have found evidence that suggests that the el

In option D Is there actually a parallelism issue? Since if we place the stem after 'that' then:
.....to suggest that | elephant had descended from an aquatic animal

.....to suggest that | elephant's trunk originally evolved as a kind of snorkel.

Please help.

Good question. You're right: "the elephant had descended" and "its trunk originally evolved" could technically be parallel clauses in choice (D).

But the second "that" in choice (E) makes it easier for the reader to see that "to suggest" is the stem ("Australian embryologists have found evidence to suggest that [clause 1] and that [clause 2]").

This, in turn, makes it easier to understand that the evidence suggests two things: 1) that the elephant is descended from an aquatic animal and 2) that the elephant's trunk originally evolved as a kind of snorkel.

Is the parallelism in (D) technically wrong? No. But the parallelism in (E) is much better.

I hope that helps!
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Hi Experts GMATNinja KarishmaB

In (E)

Isn't the "its" a bit ambiguous? In can refer to "aquatic animal"?

'Its trunk,' the subject of this clause correctly refers to the subject of the parallel clause 'the elephant.'

Australian embryologists have found evidence to suggest
- that the elephant is descended from an aquatic animal and
- that its trunk originally evolved as ...

There is no ambiguity here. We are giving details about the elephant only. Logically also, only the elephant has a trunk.
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There are two things that the embryologists have found – the elephant is descended from an aquatic animal and that its trunk originally evolved as a kind of snorkel (to help breathe under water). We know that now the trunk doesn’t work as a snorkel.

The ‘that suggests/suggesting/to suggest’ are all acceptable.

embryologists have found evidence that suggests …
embryologists have found evidence suggesting …
embryologists have found evidence to suggest …

Each of these implies that evidence shows the two characteristics pointed out above.

(B) that has suggested the elephant descended from an aquatic animal, its trunk originally evolving

We would not prefer ‘that has suggested’ because it indicates completion of an action. But the evidence still continues to suggest. Hence (B) is not correct.

(C) suggesting that the elephant had descended from an aquatic animal with its trunk originally evolved
(D) to suggest that the elephant had descended from an aquatic animal and its trunk originally evolved

Now let’s look at the descended/is descended/has descended differentiation.
'descended/has descended' has an active meaning and it implies 'to move down' or 'sink in terms of morals.'

She descended the stairs
She has descended the stairs.
The lawyer has descended to the level of his clients.
(The action of going down is performed by the subject.)

When talking about ancestry, we use 'is descended' because the action is performed on the subject.

The elephant is descended from an aquatic animal.
(The elephant did not do the descending on its own.)

Check out similar usage on other verbs:
The kids have eaten the chocolates. (active)
Chocolates are eaten by kids. (passive)

Hence, the correct usage here is ‘is descended.’ Options (B), (C) and (D) are incorrect.

(A) that suggests that the elephant is descended from an aquatic animal, and its trunk originally evolving

Also, we need to use the past ‘evolved’ because its trunk evolved as a kind of snorkel in the past. Hence, options (A) and (B) are incorrect.

We are left with answer option (E).
Answer (E)
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