Answer:
The distributive property is used when we have to multiplicate a parenthesis:

So the corrects andwer is A) 3x + 4(y-z) = 3x + 4y - 4z, because:

B is incorrect, as

C is correct, as a number plus his opposite is always 0.
D is correct, but that's the associate property as it's correct that for any three numbers of an associative set, there's another operation with verifies the equality.