Use of participle

[navdeep_bajwa]

In the remote western province of China, the prevailing price for a large bowl of noodles, which are a staple in the region, rose from 27 cents to 31 cents overnight, prompting allegations that noodle shop owners had colluded to fix their prices.

A rose from 27 cents to 31 cents overnight, prompting allegations that noodle shop owners had
B rose from 27 cents to 31 cents overnight, and prompts allegations that noodle shop owners had
C had risen from 27 cents to 31 cents overnight, prompting allegations that noodle shop owners
D had risen from 27 cents to 31 cents overnight, prompting allegations that noodle shop owners had
E raised from 27 cents to 31 cents overnight, prompting allegations that noodle shop owners had

Why B is wrong and A is wright

The explanation given by MGMAT is prompts is a present tense in B what is the verb in A as prompting is a participle and cannot act as a verb Does A has a verb

[jeromecukier]

I don't know the official reason why B is wrong and A is right but I see a few:

prompts is in the present tense, which is against the tense consistency of the phrase (rose, had colluded).
"prompted" could have been considered, but prompts is out.
you could argue, even if those price raises happened in the past, we could examine them today and conclude today that there has been price fixing. But if that was the logic of the sentence, then it wouldn't be allegations that would be prompted now, but something stronger, like evidence or conclusion.

then there is that "and".
in A, prompting establishes a causal link between both propositions, which is lost with the phrasing of B.

... so, "which prompted" could have been valid, but "and prompts" is not.

[RonPurewal]

jerome got one thing right and one thing wrong. first, the thing jerome got right:

in A, prompting establishes a causal link between both propositions, which is lost with the phrasing of B.

absolutely correct. the correct answer in this problem is a perfect example of the valid usage of the COMMA -ING modifier.

for more on the COMMA -ING modifier, click here:
post30766.html#p30766

in this case, the result described by the participle is a direct consequence of the action described in the main clause. in fact, the only construction that really conveys this concisely is the COMMA -ING modifier, so this answer choice is perfect.

--

and now, for the thing that jerome got wrong:

... so, "which prompted" could have been valid

nope. incorrect.
the pronoun "which" can only be used to refer to the noun IMMEDIATELY PRECEDING the comma. in this case, that's clearly impossible, since there is not even a noun in that location (the word "overnight" appears in that position).