Top Pair, Draw-Heavy Board and LAGs

[atnels]

Here's a general question.

Table is loose preflop, aggressive postflop. Not any especially good players, and no maniacs, but people are betting draws strong and hanging around to chase them.

Hero has A[img]/images/graemlins/heart.gif[/img] 2[img]/images/graemlins/heart.gif[/img] in the SB.

5 limpers to Hero, who completes. BB checks.

Flop (7 SB) A[img]/images/graemlins/spade.gif[/img] 8[img]/images/graemlins/diamond.gif[/img] 9[img]/images/graemlins/diamond.gif[/img]

Here's my question: You have top pair, no redraws.

Action is to Hero, what is the line?