The correct answer is enter inhibitors or fusion inhibitors.
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Enter inhibitors are a class of <span>antiretroviral drugs, used for the treatment of </span>HIV infection. Enter inhibitors interfere with the binding, fusion and entry of a virus to a human cell by <span>binding to human cellular co-receptors.</span></span>
<span>B) reproduce asexually and at a fast rate. </span>
A, An ancestor of whales had legs. Hope i helped! :D