The correct answer is D. principle of segregation
The principle of segregation is also called 'law of purity of gametes'. During gamete formation, these two factors (Aa) as per question will separate or segregate in two different gametes. A gamete carries either ‘A’ or ‘a’ gene. On self- fertilization heterozygous parent (Aa) can produce offspring AA when male and female both the gametes carry ‘A’ gene, similarly offspring with aa can be produced when male and female both the gametes carry ‘a’ gene.
