Hello Everyone!
Let's take a closer look at this question and decide how to narrow it down to the correct choice quickly! To start, here is the original question with any major differences between the options highlighted in orange:
Unlike the original National Museum of Science and Technology in Italy, where the models are encased in glass or operated only by staff members, the Virtual Leonardo Project, an online version of the museum, encourages visitors to "touch" each exhibit, which thereby activates the animated functions of the piece.
(A) exhibit, which thereby activates
(B) exhibit, in turn an activation of
(C) exhibit, and it will activate
(D) exhibit and thereby activate
(E) exhibit which, as a result, activates
After quickly glancing over the options, there are a couple places we can focus on to start narrowing down options:
1. Transition after "exhibit:" ,which / ,in turn / ,and / and / which, as a result
2. Vert tense & parallelism: activates / activation / activate
Let's start with #1 on our list: how to proceed after the word "exhibits." This problem mainly focuses on making sure we use transitions and modifiers correctly:
(A) exhibit, which thereby activates
This is INCORRECT because adding the comma + which turns the phrase into a modifier. Any comma + which modifier must refer back to the closest preceding noun, which in this sentence is the exhibit. Does the exhibit activate the animated functions? NO! The person's touch activates it! So let's rule out this option.
(B) exhibit, in turn an activation of
This is INCORRECT because using the phrase "in turn an activation of" doesn't really make sense. First, the phrase "in turn" can only be used to introduce new clauses, which would need their own nouns and verbs to work. In this case, the phrase "in turn an activation of..." is missing a solid verb for it to make sense, so let's rule this one out as well.
(C) exhibit, and it will activate
This is OKAY for now. It's clear that the touching and activating of the animated functions happen, for the most part, at the same time. Both items use parallel structure by using singular verbs (touch/activate), so let's keep this one for now.
(D) exhibit and thereby activate
This is OKAY for now. It's also clear that we're talking about two actions the people are performing (touch/activate), and both are worded using parallel structure. Let's keep this one for now.
(E) exhibit which, as a result, activates
This is INCORRECT because, yet again, we have a "which" modifier used incorrectly. This sentence suggests that the nearest noun (exhibit) activates the animated functions, which isn't correct - the people do this through their touch. So let's rule this out.
We can eliminate options A, B, and E because they all created confusing or misleading modifiers. Now that we've narrowed it down to only 2 options, let's take a closer look at each one to determine which is the best option:
(C) exhibit, and it will activate
This is INCORRECT because it contains a vague pronoun! What is the word "it" referring back to: the touch, the visitors, the exhibit? It's not clear, so we need to toss out this option. The GMAT really doesn't like vague pronouns, so whenever you see one, it's a good indicator that you're looking at a wrong option!
(D) exhibit and thereby activate
This is CORRECT! By using the word "and," the sentence is clearly showing that the visitors are doing 2 actions: touch the exhibit and activate the animated functions. Both actions are worded using parallel structure by using singular verbs (touch/activate). It is clear and concise, just like the GMAT prefers!
There you go - option D is the correct choice!
Don't study for the GMAT. Train for it.
