"Kill not the goose that lays the golden eggs." What does the sentence mean？ （)

A、It is better to accept something small than to reject it and hope to get more later on.

B、If too many people try to do the same thing at the same time, there will be chaos.

C、Anyone who claims more than he has already got is very likely to get nothing at all in the future.

D、There must be something better after every piece of unpleasantness.