In an automobile negligence action by Popkin against Dwyer, Juilliard testified for Popkin. Dwyer later called Watts, who testified that Juilliard's reputation for truthfulness was bad. On cross-examination of Watts, Popkin's counsel asks, "Isn't it a fact that when you bought your new car last year, you made a false affidavit to escape paying the sales tax?" This question is 
proper, because it will indicate Watts's standard of judgment as to reputation for truthfulness.  proper, because it bears on Watts's credibility.  improper, because character cannot be proved by specific instances of conduct.  improper, because one cannot impeach an impeaching witness. 