PT 65 S3 Q17

Which one of the following is a statement that is true ofblackmail under ... ...

Which one of the following is a statement that is true of blackmail under Canadian and U.S. common law, according to passage A, but that would not have been true of blackmail in the Roman legal context, according to passage B?
(A) It combines two acts that are each legal separately.
(B) ...
(C) ...
(D) ...
(E) ...

*This question is included in Dec 2011 LSAT (PT 65): Reading Comprehension