Whenever you multiply number by another number smaller than 1 (but greater than 0), result will be smaller than original number.
For example: 1 × 0.99 = 0.99 (see, 0.99 is smaller than 1)
So multiplying 6.3 by 0.01 will be smaller than 6.3 itself.
So to answer your comment on your question, it's C.
