The answer is 2-to-the-power-of-n, since for every input, the number of different combinations doubles. From your list I think answer A is meant to indicate 2ⁿ.
Answer:
The correct option to the following question is option (A).
Explanation:
SISD is used in the uni-processors systems which executes an individual instruction streams at a time by which we control an individual memory for the storage of data.
It is the flow or the sequence of an individual data or instructions which controlled on the systems.
Whereas SISD is different from the SMID and it is not used in the Uni-processor systems