Answer:
Notice that in the expression n - 8,
the eight is the thing being subtracted.
We could read it like this: "Eight subtracted from a number."
So we can immediately see that the last option is not correct. It's the opposite of what we want. The third option is the same as the last, just worded differently: The number 8, decreased by a number n.
The second option is correct: A number n, but eight fewer than that.
n - 8
