The correct statement is:
Mendelian inheritance concerns genetic traits that are controlled by only two alleles, while non-Mendelian inheritance is controlled by multiple alleles.
Mendelian inheritance, based on the principles established by Gregor Mendel, typically refers to traits controlled by single genes with two alleles (dominant and recessive), while non-Mendelian inheritance includes more complex patterns such as multiple alleles, gene interactions, and polygenic inheritance.