statics question?!

Question

A body is placed on an inclined rough plane and it was about to slide. When the inclination angle to the horizontal is increased, the body moved downward , then the friction force at this moment ...........

a) vanished.

b) decreases.

c) increases.

d) increases to infinity.

## I need the solution with detailed steps (why) ##

Answer 1

As an object enters a state of motion, we switch from having static friction to kinetic friction. The kinetic friction is always less than the static friction but grater than 0, so the answer is b.