Answer :
ok so the degree is the highest exponent of the placeholder
-9=-9 times 1
since there is none, degree is 0
or
x^0=1 so
-9x^0=-9
0 degree
answer is B
-9=-9 times 1
since there is none, degree is 0
or
x^0=1 so
-9x^0=-9
0 degree
answer is B