Here os the OE:

(Appropriate Preposition) Two of the choices have the expression “grounds to,”
while one has “grounds for.” Two other choices introduce full subordinate clauses.
This indicates that there is perhaps an error relating to the use of a wrong preposition.
The correct preposition to combine with “grounds” is “for” and not “to.” (What were
the grounds cited by the magistrate for the acquittal of the accused? What are the
grounds for your suspicion that George is dishonest?) So, (A) is wrong.
(B) also has the same error, and can be discarded for that reason.
(C) has the idiomatic phrase “grounds for sympathizing with,” and is the answer.
Always consider a phrase more idiomatic than a clause—so you can easily reject
both (D) and (E) as being less elegant than (C).

If you find my question helpful, you can give KUDOS. Thanks

why B is wrong?
"to simpathise..." is used to show the intent of the main clause and is correct. In this way, "to simpathize..:" modify the previouse clause. Why it is wrong?

"grounds for" is the correct idiom ..So Option C is the answer

Hello from the GMAT Club VerbalBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.