The fragile markets were caught off-guard Friday by an unexpected drop in retail sales for May, which renewed concerns about the pace of the recovery in the United States.[b][/b]

a. which renewed concerns about the pace of the recovery in the United States.
b. an event that renewed concerns about the pace of the recovery in the United States.
c. and renewed concerns about the pace of the recovery in the United States.
d. renewed concerns about the pace of the recovery in the United States.
e. renewing concerns about the pace of the recovery in the United States.

Can you please explain how E can be correct?
You can't say
The fragile markets were caught off-guard Friday by an unexpected drop in retail sales for May, renewing concerns about the pace of the recovery in the United States.
because it won't be correct to swap the phrases and say
Renewing concerns about the pace of the recovery in the United States, the fragile markets were caught off-guard Friday by an unexpected drop in retail sales for May

I thought if you use a comma + "ing", you should be able to swap the sentences and they should still make sense.

Wouldn't the correct answer be The fragile markets were caught off-guard Friday by an unexpected drop in retail sales for May renewing concerns about the pace of the recovery in the United States.
- without the comma before renewing????

Thanks

can someone explain me whats the problem in B...I feel the noun +noun modifier modifies either the preceding noun or cluase ..here it modifies the clause..So on what basis option B is an incorrect answer?
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hi,
In option B noun +noun modifier always just add an additional information abt the precedding noun or clause.But as per the intended meaning of the sentence
The fragile markets were caught off-guard Friday by an unexpected drop in retail sales for May" this resulted in the "renewing concerns about the pace of the recovery in the United State"
So its logical to use renewing(verb+ing modifer) when the intended meaning of sentence is the result of preceding clause
hope this helps
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It`s a modifier problem.Answer is E.according to ing modifier describes the clause or shows the effect of the clause.here the modifier describes the clause.