Answer:
Out of all the ideas postulated by Gregor Mendel as stated above the one that requires at least two genes to be demonstrated is “Genes assort independently in diploids.
Explanation:
A cell that contains two sets of chromosomes is called as the diploid cells. Mendel has stated that genes assort independently in diploids i.e.
The allele a gamete received for one gene does not in any way influence the allele received for another gene. Hence at least two genes is needed for its demonstration.