Question

what does it mean if someone is heterozygous for a trait? they have more than two alleles for that trait. they do not have any alleles for that trait. they have two identical alleles for that trait. they have two different alleles for that trait.

Explanation:

In genetics, heterozygous refers to having two different alleles for a particular gene - trait. Homozygous is having two identical alleles. Having more than two alleles for a trait is not the definition of heterozygous, and having no alleles is not possible for a trait one expresses.

Answer:

They have two different alleles for that trait.