ALM & AO for plan deficit

2014 AM exam, question 5C: The plan turns from surplus to deficit, and the question is ALM or AO would help to eliminate the plan deficit status without making additional contribution.

I do agree with the proposed answer that the ALM will no help, but AO will do eliminate the deficit status.

My question is if the plan turns into deficit, ALM should be automatically forced in use? If not, AO will be accepted under which conditions? Is there any past questions relevant to such situation?

Thanks!

The point is that with a deficit, ALM won’t work (to eliminate the deficit), while AO might work. (Granted, AO also might make the deficit larger.)

Given this, AO should be the clear choice.