Answer:
d. to allocate goods when there is a price ceiling.
Step-by-step explanation:
Non price rationing or queuing is a measure used when there is a price ceiling, queuing is used to arrange people on a first come first serve basis.
Rationing is done on the non monetary cost of waiting in line.
Waiting time eventually balances buyer equillibrum. When customer's are waiting on queues for too long some of them loose interest and leave, this restoring balance between what is available and number of people waiting to buy.