While some propose to combat widespread illegal copying of computer programs by attempting to change people's attitudes toward pirating, others by suggesting reducing software prices to decrease the incentive for pirating, and still others by calling for the prosecution of those who copy software illegally.
(A) by suggesting reducing software prices to decrease the incentive for pirating, and still others by calling
(B) by suggesting the reduction of software prices to decrease the incentive for pirating, and still others call
(C) suggest the reduction of software prices for decreasing the incentive for pirating, and still others call
(D) suggest the reduction of software prices to decrease the incentive for pirating, and still others by calling
(E) suggest reducing software prices to decrease the incentive for pirating, and still others are calling

Source : OG 10th Edition - SC - 160 ..

This question i sno more in later editions , so this could be the reason tt question is not good .

Note: I didn't actually indicate whether I thought this one was good or bad. I just said that I wouldn't study from questions for which I didn't know the source. One of the reasons is that the source might be bad, but there are other good reasons as well (as I noted in my post).

Some of the old paper test questions (from 13+ years ago) are "too old" in my opinion and don't reflect the current CAT anymore, but I don't think OG10 is bad. They do obviously have a reason for dropping a question from future editions, so there's probably some reason why they didn't think this one was as representative any more, but we can still probably learn from it.

Okay, I can't discuss this problem directly because we're not supposed to discuss OG problems online, but we can discuss similar problems...

While some propose to study by working on their own, others by taking a class, and still others by finding a tutor.

That shorter sentence might help you to see one major problem with the original. It's not actually a sentence.

"While some propose to study by working on their own" can't be changed. It's not a complete sentence, so what follows the comma has to provide the complete sentence somewhere.

There's also some obvious parallelism going on there, but what's actually supposed to be parallel? The subject of the first cluase is "some" and then the next two use "others" and "still others." The subjects, then, are not the same. So each subject needs its own verb - ah, that's where the parallelism needs to start, not with the "by working" etc parts!

Some propose
others <suggest>
still others <call or are calling>

Elim A, B, D.

C says "suggest the reduction of something for decreasing something else"
When you reduce one thing for the purpose of decreasing something else, you say "reduce this thing TO DECREASE this other thing." Think of the "to" as "in order to."

Hmm. And this is why I think they probably eliminated this one in future editions. E is better than C, yes, but it's better for fuzzy "idiomatic" reasons. A native speaker would tell you "This is just the way we say it (E, not C)." That's not a great reason.