Question

Tropical bats play important roles in the rain forest ecosystem, aiding in the dispersal of cashew, date, and fig seeds; pollinating banana, breadfruit, and mango trees; and indirectly help produce tequila by pollinating agave plants.

Option A
Option B
Option C
Option D
Option E

(This question is from Official Guide. Therefore, because of copyrights, the complete question cannot be copied here. The question can be accessed at GMAT Club)

Solution

Sentence Analysis

  • Tropical bats play important roles in the rain forest ecosystem, (Main clause. Subject – “Tropical bats”; Verb – “play”)
    • aiding in the dispersal of cashew, date, and fig seeds; (First verb-ing modifier modifying the preceding clause. How they play important roles? By aiding…)
    • pollinating banana, breadfruit, and mango trees; (Second verb-ing modifier modifying the preceding clause)
    • and indirectly help produce tequila by pollinating agave plants. (To maintain parallelism, this part needs to be a verb-ing modifier modifying the preceding clause)

The sentence says that Tropical bats play important roles in the rain forest ecosystem. How? By doing three things described in a list of three verb-ing modifiers. As we can see the three elements are separated by semi-colons and not commas. Why? Because the elements themselves contain commas. So, using commas to separate these three elements would create confusion.

Rather, separating elements in a list in which the elements themselves contain commas is one of the uses of a semi-colon.

The error in the sentence is a lack of parallelism in the third element. To maintain parallelism, the third element needs to be a verb-ing modifier.

Option Analysis

(A) Incorrect. For the lack of parallelism described above.

(B) Correct.

(C) Incorrect. The clause “they indirectly help” is not parallel to the other two verb-ing modifiers. Also, if the intention were to present this information as a separate clause, then it needs to be joined with the previous clause using “comma + and” (Two independent clauses cannot be joined with just “and”). Also, presenting this information as a separate clause creates an additional error. There are only two members in the list: “aiding” and “pollinating”. These two members need to be joined with “and”, not with a comma.

(D) Incorrect. For the lack of parallelism.

(E) Incorrect. For the lack of parallelism. Also, “helping the producing of” is an awkward expression compared to “helping to produce”.

This solution was created by Chiranjeev Singh and Anish Passi.