Answer:
chestnut
Step-by-step explanation:
In horses, having chestnut hair (E) is dominant over having black hair (e). If a homozygous dominant parent (EE) is crossed with a homozygous recessive parent (ee), the Punnett square will show that all of the offspring will have the genotype Ee (heterozygous).
Since the chestnut hair trait is dominant, all of the offspring will express the phenotype of chestnut hair, regardless of their genotype.
Therefore, each offspring will have chestnut hair.
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