Which types of phenotypic ratios are likely to occur in testcrosses when dealing with two gene pairs for which all the genotypic combinations are of equal viability?
A)2:3,1:2
B)1:1:1:1
C)1:2:1,3:1
D)9:3:3:1,27:9:9:9:3:3:3:1
E)12:3:1,9:7

Question

Quizplus · Accepted Answer

When all genotypic combinations are of equal viability, a 1:1:1:1 phenotypic ratio is expected in a testcross with two gene pairs.

Which Types of Phenotypic Ratios Are Likely to Occur in Testcrosses