Question

Test cross involves

• A. Cross between two $F_1$ progenies
• B. Crossing $F_1$ progeny with double recessive parental progeny
• C. Crossing genotypes with recessive traits
• D. Crossing two genotypes with dominant traits

Answer 1

The correct option is B Crossing $F_1$ progeny with double recessive parental progeny

• The crossing of an F${}_1$ progeny with a double (homozygous) recessive parental progeny is done in order to determine whether the progeny is homozygous or heterozygous for a character under consideration.
• This is called a test cross. It was first introduced by Gregor Mendel.
• Those that are heterozygous will have one dominant and one recessive allele individuals and those that are homozygous dominant will have two dominant alleles, and those that are homozygous recessive will have two recessive alleles.

Thus, the correct answer is option B.