Option D
The simplified version of 7x − 4(x − 8) = 56 is 3x + 32 = 56
Solution:
Given expression is:

Use distributive property to simplify the expression
By distributive property,
a(b + c) = ab + ac
Therefore,

Combine the like terms : 7x - 4x = 3x
Therefore,

Thus option D is correct