Question

17 multiple choice 1.5 points in a regular dihybrid cross, a ratio of 9:3:3:1 is observed. in one experiment, a researcher observed a ratio of 9:3:4. this is likely a result of incomplete dominance codominance epigenesis epistasis

Explanation:

In a dihybrid cross, a 9:3:4 ratio is a modified Mendelian ratio often due to epistasis, where one gene masks or modifies the expression of another gene. Incomplete dominance and codominance affect the phenotype expression of alleles at a single - gene locus and do not typically result in this ratio. Epigenesis is a broader concept related to the development of an organism from an egg and is not related to this genetic ratio.

Answer:

D. epistasis