Answer: C. 64
Explanation:
We know that the number of total elements in the sample space is given by :_
, where N is the number of total possible outcomes for an event and n is the number of times event is repeated.
Given: The number of equally likely sample outcomes of a single stage of an experiment = 4
The number of stages in the experiment = 3
Then , the total number of elements in the sample space :-

Hence, the total number of elements in the sample space = 64.