Answer :
When an unbalanced force acts on an object, the object accelerates. We can immediately rule out B and D, as friction changes based on the material and by applying a force the net force can’t be zero. It can be easy to say that the object will speed up after the force is applied (and it often does!), but take a braking car, for example. An external force of friction is applied to the brakes, causing an acceleration but in such a fashion that the car slows down. So, although an object can speed up after a force is applied, it isn’t always guaranteed.
Hope this helps!