Leat common multipule of 24 and 40?

To determine the least common multiple of 24 and 40, you need to list out the multiples for each number until a common multiple is identified.
 
For 24, the first five multiple are 24, 48, 72, 96 and 120.
 
And the first three multiples of 40 are 40, 80 and 120.

The first common multiple is 120.

Hope this helps you =)

I'm sure the answer is a