A cross involving parents differing only in one trait is:
A. Haploid – Organisms with one set of chromosomes.
B. Diploid – Organisms with two sets of chromosomes
C. Monohybrid – A cross is made between two parents differ on the basis of one trait is called Monohybrid.
D. Dihybrid – A cross is made between two parents differ on the basis of two traits is called Dihybrid.
So, the correct answer is option C.