When in object moves stop moving changes speed or changes direction how do scientist describe that condition?

im taking test rn nd this question was on there, im saying unbalanced force, if it not correct i will put right answer, but im pretty sure the answer is unblanced

i think the right answer is unbalanced

f=gm1m2/d^2 it d

f is force g is gravitaiton constant, m1 is mass of first object, m2 is mass of second object. d is distance between two object

d eras and periods