Which type of bread molds the fastest?

One way to estimate how quickly bread will mold would be to look at its
water content. For example the percent of water in several breads is:
Navaho fry bread 26%, banana bread 29%, toasted white bread 30%,
plain white bread 36%, Oat bran bread 44% and canned Boston brown bread
47%.

The rate at which a bread can mold depends on following-
Humidity
temperature
darkness

So if you want a bread to mold fast [so as to show as an experiment] spray some water [just a little] and put it in an airtight box and leave it in a warm and dark place. You will see that this is an ideal place for bread to develop mold.

It is easy white bread molds the fastest i would know this because i did a project on it