Preflop quiz

What's your play?

9-max · 12 bb
Pot 4.62 bb
UTGopen
2
MPfold
HJfold
COfold
BTNfold
D
SBfold
0.5
BB12.5 bb
A♠J♠

A player opened, you're in the BB.

The answer comes from Exploit It's full preflop tree, the same one behind the Solver page and Play mode: chip-EV equilibrium, every position at the table, no ICM. EVs are counted from the start of the hand, posted blinds included. An action played at equilibrium, even rarely, counts as perfect.