I think the answer is:
2 x _ + 3 = 4 x _ - 3
A. 0 is incorrect because 2 x 0 = 0 + 3 = 3 and 4 x 0 = 4 - 3 = -3
B. 1 is incorrect because 2 x 1 = 2 + 3 = 5 and 4 x 1 = 4 - 3 = 1
C. 3 is correct because 2 x 3 = 6 + 3 = 9 and 4 x 3 = 12 - 3 = 9
D. 5 is incorrect because 2 x 5 = 10 + 3 = 13 and 4 x 5 = 20 - 3 = 17
E. 7 is incorrect because 2 x 7 = 14 + 3 = 17 and 4 x 7 = 28 - 3 = 25
Therefore C is correct.
