Unused bitmaps in resource, help?

I create an application that uses many bitmaps in its resource. There are 4
groups of bitmaps, but only one of them is used by the application at a
time. So the other 3 groups aren't loaded. Each group is 1.2MB, and the
program is 300KB --> Total program's size: 5.1MB

My question is: How will the program handle this? Will it allocate memory
for all bitmaps there are in resource, or only for bitmaps that are loaded
at the time? Thanks.

-- Ivan