Can Someone help me?

I believe the answer A.

Step-by-step explanation:

A coin has 2 sides - heads and tails.

A fair number cube has 6 sides - 1, 2, 3, 4, 5 and 6.

When doing a tree diagram, you show all the possible outcomes that you can get.

The other options either have missing numbers from the cube, a missing side from the coin, or both.

Hope this helped. :)