Opponent’s options: FAILING/FALLING/PALLING b8, PLAITING/ANTIPILL/FLATLING/PLAINTIFF row 2
Candidate plays: QI h1 (35), QI f1 (17), TI 2g (2), Blocking plays on column 2

Subgoal: Minimize the number of opponent bingos, or outrun your opponent’s bingo.

Resolution: Since your opponent played off a U and is potentially “protecting” column b, you should assume they have a strong bingo rack, like AILING or FLLING and thus should weight towards blocking. If your opponent has something like PLAITING, you should still win by being able to play QI. As such, you’re best off making a blocking play such as LAC 9a (8).