Player A is UTG
Player B is in CO
Pre-Flop
Player A limps, folds, Player B raises to 4x BB, folds, Player A calls.
Flop
:2d: :8c: :8h:
Player A checks, Player B bets 2/3 pot, Player A min-raises, Player B calls.
Turn
:jd:
Player A checks - What is this a sign of?
Assume neither player is an extreme LAG or TAG and 100BB stacks.