Commercial chicken breeders will cross two different breeds of chickens (e. g., white rocks and white cornish) to create a fast growing chicken that is larger than either of the parental breeds. this result is best explained by the phenomenon
a. hybrid vigor.
b. incomplete dominance.
c. epistasis.
d. both a and b
e. both a and c

A: hybrid vigor

Explanation:

Hybrid vigor is the improved morphological and physiological functions that are usually observed in resulting offspring when  genetically dissimilar organisms of the same species are mated or crossed with each other.

Hybrid vigor is otherwise referred to as heterosis or outbreeding enhancement, and it is in contrast to inbreeding depression - the reduction in fitness or functions witnessed when genetically related organisms are mated.

Hybrid organisms combine the desirable functions in the two parents, resulting in an improved features when compared to the parents.

The correct option is A.

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