bharath2787 wrote:Sam Barr, and postdoctoral scholar, Greg Hill, are conducting experiments to see whether ozone can alter potassium channels in guard cells using an electrophysiological tool called patch clamping.

A. to see whether ozone can alter potassium channels in guard cells using
B. to see whether ozone can alter potassium channels in guard cells by the use of
C. to see if ozone can alter potassium channels in guard cells with using
D. that see that ozone is able to alter potassium channels in guard cells using
E. that see whether ozone are able to alter potassium channels in guard cells using

OA is A . i think OA is also wrong . could someone please explain ?

Dear Bharath,
You are perfectly correct. The source says (A) is the OA, that version is an absolutely rotten sentence, something that would clearly be a trainwreck wrong answer on the real GMAT. No other choice fixes the fundamental problems. This is, at core, an absolutely horrible question. Don't worry, my friend. The problem is NOT your understanding. The problem is the question itself.

The principle problem with (A), of course, is the misplaced modifier. See this blog for more on misplaced modifiers:
https://magoosh.com/gmat/2013/modifiers- ... orrection/

My friend, I would caution you. Not all GMAT practice questions are of the same quality: there is absolutely fantastic material out there, and there's some horrible stuff. In a search, I found this question posted on a free site. Did you ever hear the sarcastic expression "free and worth the price"? MGMAT has excellent questions, for example.

Here's a high quality SC question to practice:
https://gmat.magoosh.com/questions/3292

Let me know, should you have any further questions.

Mike