IMO, B is correct.
This question tests us about "perfect infinitive - TO HAVE + PAST PARTICIPLE" vs "infinitive - TO + VERB"
Perfect infinitive mentions an action that happened in the past and still has its effect in present. However, infinitive mentions an action that happens in present or will happen, but DID NOT happen in the past.For example: Mr. John is known to have worked for IBM since 1990.
What if we use a more concise sentence: Mr. John is known to work for IBM.
The difference is the first sentence mentions that Mr. John started working for IBM in 1990 and he still works the the company
The second sentence mentions that Mr. John is going to work for IBM. it changes the intended meaning.When you see the PERFECT INFINITIVE, please make sure you checked the time of an action.
If it happened in the past and still bear an effect in present ==> Perfect infinitive is correct, even the sentence is longer and not concise.
Back to the question, the first part is "The fear of rabies is well founded"
==> it provides the evidence that the action happened in the past. Clearly, in the second part, we cannot use infinitive-to recover. If there is no first part, the second part only maybe
Between A & B, A is wrong for reason above. B is correct.PS:
You will see a lot of this structure - To have + P.P in real GMAT, because GMAT hopes you will pick a more concise sentence and get it wrong
Hope it helps.
Please +1 KUDO if my post helps. Thank you.
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