During the diving when a diver jumps off from platform he brings her knees and arms closer to the body
This is because when diver is in air he don't have any torque about his center of mass which shows that angular momentum of his body will remain constant during his motion in air
Now we can say product of his moment of inertia and his angular speed will remain constant always
So here if we decrease the moment of inertia of the body during our motion then angular speed will increase so that product will remain constant
and this is what the diver use during his diving
so correct answer will be
It decreases her moment of inertia.
