Class 12 NEET Biology Principles of Inheritance and Variation Questions Part 2

The test cross involves the crossing of F1 hybrid with a double recessive genotypic parent.
By test cross, the heterozygocity and homozygocity of the organism can be tested.
Thus, the offspring will be 100% dominant, if the individual which crossed with recessive parent i.e., (tt) was homozygous dominant and ratio will be 50% dominant and 50% recessive so that proves individual was heterozygous dominant. so , answer is option C .