Half of the gametes produced by an organism with the genotype Aa will receive the A allele, while half will receive the a allele. What process produces such results?

This is known as segregation.

Explanation:

Segregation may be defined as the process in which the progeny receive half number of chromosomes from its father and half number of chromosomes from its mother.

The alleles may segregate at the time of formation of gametes so that the individual maintains the law of purity of gametes. The segregation law was given by Mendel.

Thus, the correct answer is segregation.