Question

a chestnut - colored horse is mated with a cremello (cream - colored) horse. over a 10 - year period, all of their offspring are palominos. this pattern of inheritance is best explained by
a environmental effects on genes
incomplete dominance
multiple gene effects
complete dominance

Explanation:

In incomplete dominance, the heterozygous offspring show an intermediate phenotype between the two homozygous parents. Here, chestnut - colored and cremello horses produce palomino offspring which is an intermediate phenotype, indicating incomplete dominance. Environmental effects on genes would imply external factors influencing the phenotype rather than a genetic inheritance pattern. Multiple gene effects involve multiple genes contributing to a trait. Complete dominance would result in offspring showing the phenotype of one of the parents.

Answer:

incomplete dominance