"under central planning, some group has to decide how to get the necessary inputs produced in the right amounts and delivered to the right places at the right time. this is a nearly impossible task without markets and profits." this quotation best identifies the: incentive problem under central planning. coordination problem under central planning. self-sufficiency dilemma under communism. resource over-commitment problem under communism.

Coordination problem under central planning.  
Let's look at the available options and see what makes sense given the question conditions. 
 Incentive problem under central planning.
 * The quote says absolutely nothing about whether or not the people are willing to perform the work and since incentive deals with willingness to perform, this is obviously and incorrect choice. 
 Coordination problem under central planning.
 * Getting the inputs delivered is definitely a coordination issue. So this is the correct choice. 
 self-sufficiency dilemma under communism.
 * Nothing in the quote is associated with self-sufficiency. So this is bad choice. 
 resource over-commitment problem under communism.
 * You might be able to stretch things to claim that inputs are resources. But option number 2 is a better choice. So this too is a bad choice.

You can tell by just looking at it