Answer:
Choice A, 20(3n-m)
Explanation:
First, lets combine like terms for the question 54n - 20m + 6n,
60n - 20m.
Next, lets rule out the choices that are visibly wrong. This includes Choice B, because it wouldn't equal what is above and Choice C, as it ignores unlike terms.
Now, it is down to Choices A and D. Let's use the distributive property to simplify these options.
Choice A:
20(3n-m)
60n-20m
Choice D:
20(m-3n)
20m-60m
With this, it can be concluded that the correct answer is Choice A since it equals 60n-20m, which is equal to the original question when like terms are combined.