Answer : A (-3 + 3) , B (7 + (-7) ) and C (-9 + 9)
The two numbers that are being added need to be additive inverses of each other for the result to be zero. That is, if one number is positive, the other should be negative, and vice versa, with equal absolute values.
Since -3 + 3 equals 0, -3 and 3 are additive inverses of one another in option A.
Since 7 + (-7) = 0, 7 and -7 are additive inverses of one another in option B.
Since -9 + 9 equals 0, -9 and 9 are additive inverses of one another in option C.
7.4 + 7.4 is not the same as option D.
Option E, 45 plus (-54), is not the same as 0.
Hope this helps, have a nice day!