Which of the following best describes the forces when there are different-sized forces from opposite directions acting on an object?
positive
negative
unbalanced
gravitational

Unbalanced force

Explanation:

When several forces are acting on an object from different directions such that the all the forces are of different magnitudes and all forces have different directions

Then in that case the sum of all forces on the object will be given by vector sum of all forces on it

so here we will have net force on the system is unbalanced as all the forces are of different magnitudes

so in that case we can say

so sum of all above forces is non zero so it is known as unbalanced forces

the answer would be a

their crystal patterns have been disrupted by stress