GMAT Sentence Correction (SC) | Re: Although the rise in incidence of the disease has fueled fears for

here you need to look to 2 things:

Verb tense which is great in A but the idiom 'fear for' is wrong.

the below explained by Mitch (GMAT instructor)

X fears for Y.
Conveyed meaning:
X believes that Y is in danger.
Mary fears for John.
Conveyed meaning:
Mary believes that John is in danger.

X has a fear of Y.
Conveyed
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