We are working on a new set of Verbal Tests for GMAT Club.

Question

We are working on a new set of Verbal Tests for GMAT Club. Several members have responded to our " Help Wanted Ad " and submitted their questions. I am posting the first batch and would love to hear your feedback about the questions. I would also like to know your opinion about how close this question is to the Real GMAT (or Official Guide if you have not taken the GMAT yet) on a 1-5 scale where 
1 is not close at all
2 is not close
3 is average/undecided
4 is close 
5 is exact match

I will post the OA and Explanation in 1-3 days, depending on how many takers we get. Your feedback will help significantly and very much appreciated!

By the end of 2008,  180 countries had signed the Comprehensive Nuclear-Test-Ban Treaty (CTBT), which forbids all nuclear explosions,  including the explosive testing of nuclear weapons. 
A. 180 countries had signed the Comprehensive Nuclear-Test-Ban Treaty (CTBT), which forbids all nuclear explosions,
B. 180 countries signed the Comprehensive Nuclear-Test-Ban Treaty (CTBT), forbidding all nuclear explosions,
C. the Comprehensive Nuclear-Test-Ban Treaty (CTBT) was signed by 180 countries, which forbid all nuclear explosions,
D. the Comprehensive Nuclear-Test-Ban Treaty (CTBT) had been signed by 180 countries that forbid all nuclear explosions,
E. the Comprehensive Nuclear-Test-Ban Treaty (CTBT) was signed by 180 countries, forbidding all nuclear explosions,

--

nitya34 · Answer

Very good Q as it tests TENSE

Scale 4

Technext · Answer

Good question.

Scale ---> 4

bb · Answer

Here is the OA and Explanation:  Now that the OA and explanation are posted, can you rate this question in terms of difficulty?  
Let's keep the 1-5 scale with 1 being easy and 5 hard.

Answer:  A

Relative pronoun ‘which’ and ‘that’ refer to the noun or noun phrase that comes exactly before them. It is the treaty that forbids the testing of nuclear weapons.
A – This is the correct answer.
B – This uses the participial form to create a run-on modifier with the latter half of the sentence.
C – It is the treaty that forbids the testing of nuclear weapons and hence the relative pronoun should relate to treaty, not the countries.
D – As above
E – As above

walker · Answer

By the end of 2008, 180 countries had signed the Comprehensive Nuclear-Test-Ban Treaty (CTBT), which forbids all nuclear explosions,  including  the explosive testing of nuclear weapons.

If A is a right answer, we have non-essential part with "which" that we can omit without loses. At the same time, without "which....explosions" part, "including" part has no sense". So, " had signed  ... CTBT... including  ...testing" or " forbids ... including ...." is ambiguity.

We are working on a new set of Verbal Tests for GMAT Club.

What is the correct answer?

Prep Toolkit

Top 5 GMAT Debrief Videos

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards