Although you have not formatted the question properly I think it is
C. I suspect you meant C to be
Sometimes these are easier to spot than other times. As you practice more and more you will start to spot them more easily. If not then switch to the formula.
The constant of 5 is a prime number so we must have the structure:
I have use the
the coefficient of
It could be that the three needs to be in the other bracket. I have not yet tested it.
Notice that we have
Multiply everything in the right brackets by everything in the left brackets.
So we have: