A cat lies on the floor? can you say that no force acts on the cat? or is it correct to say that no net force?

An object has no acceleration if there is no net force on
the object.

The cat is not moving so there is no
acceleration on the cat and therefore no net forces.

I am
assuming the cat is on the earth, and so there is the force of gravity on the cat, and
an equal and opposite force on the cat from the floor the cat is laying on. So it would
be incorrect to say there were no external forces on the
cat.

I hope that helps, the correct answer is no net force
on the cat.