As the length is 6, we need to consider all the numbers less than 100.

2 is the least prime number so we can start with 2.

Number 1: 2^6 = 64
Number 2: (2^5) * 3 = 96

If we go any further by trying to reduce the power of 2, we will get a number > 100. Therfore if this is the case with 2, then defintitely the prime numbers > 2 will give one numbers > 100.

So is the answer 2. ie C

"As the length is 6, we need to consider all the numbers less than 100. "

why? I'm missing something here.

I'm sorry about the statement there. Am not too good at putting down mental thoughts.

What i meant was..

As the length is 6, and we need to consider all the two digit numbers i.e. numbers less than 100

"How many two digit integers have length 6? "

Damn , missed that part, thanks keepsmilinyaar