The correct answer is (A), please let me know if you are unable to see the correct answer. The passage tells us that the bill places the burden of proof on the plaintiff and imposes a statute of limitations, making it generally more difficult to reclaim stolen art. The author also tells us that reclamation suits have not yet been a problem (lines 25-26) but according to one of the supporter's of the bill in the absence of the statute of limitation, widespread reclamation litigation could pose a serious threat to the museums (lines 19-24). We can thus conclude that litigation has been less common than Burke fears it will become as (A) correctly states.