How many different types of gametes are possible to be formed by an individual if its genotype for a particular trait is AABbccDd?

4

The correct answer is Option (1) → 4   

Total possible gametes formed by a genotype is = 2n, where n is a number of genes for which it is heterozygous .

In  AABbccDd, number of heterozygous = 2

Total possible gametes formed by a genotype is = 2n = 2²=4