Hi hi!!
So, A is correct because it is the same equation just (3+4) is in the front. D is also correct because it is the same question because when a number is for example like 10(3+4) it mean multiplication and in this case you are multiplying. B and C are incorrect because they do not have a total of 70. The original equation, 10x(3+4) = 10x7 = 70.
Correct answers:
A. (3+4)x10
D. 10(4+3)