Question

A brown cow is mated with white cow and they produce a roan cow Roan cows are brown with white spotsWhich statement best explains this phenomenon

Answer 1

C.
In co-dominance both traits show up, and in incomplete dominance the two traits mix together.

So automatically A, B and D are wrong, since we can see both brown and white colors on the cow separately.

If it were any of those we wouldn't be able to see any of the traits alone they would be a mix.