Assuming no genetic recombination, how many genetically distinct types of gametes can a single human being make?

Explanation:

Each chromosome represents a twin.like pairs of socks.

This is an analogous problem: you have 2 pairs of socks, one white, one black. Each of the sock is tailored to a specic foot, right or left. How many different ways can the socks be mixed and matched , one for each foot?

Here are the possibilities : left = black, right = black is one such match. Left = white, right = black is another.

so also we will have 23 chromosome pairs