Rarely fatal, though extremely dangerous nonetheless herpetologists studying rattlesnake venom must exercise caution lest the unwary handled find him her herself the subject of a later cautionary tale.

(A) herpetologists studying rattlesnake venom must exercise caution

(B) the study of rattlesnake venom requires caution on the part of herpetologists

(C) caution on the part of herpetologists is necessary when studying herpetologists

(D) rattlesnake venom must be studied with caution, even by herpetologists

(E) studying rattlesnake venom requires herpetologists to be cautious