Deeb was charged with stealing furs from a van. At trial, Wallace testified she saw Deeb take the furs. The jurisdiction in which Deeb is being tried does not allow in evidence lie detector results. On cross-examination by Deeb's attorney, Wallace was asked, "The light was too dim to identify Deeb, wasn't it?" She responded, "I'm sure enough that it was Deeb that I passed a lie detector test administered by the police." Deeb's attorney immediately objects and moves to strike. The trial court should 
grant the motion, because the question was leading.  grant the motion, because the probative value of the unresponsive testimony is substantially outweighed by the danger of unfair prejudice.  deny the motion, because it is proper rehabilitation of an impeached witness.  deny the motion, because Deeb's attorney "opened the door" by asking the question. 