Answer:
C.
Explanation:
(m^2-m-3) + (m-4)
there is no like terms for m^2 so it stays the stay.
next you add -m to m because the first m is negative they cancel out leaving nothing. lastly we add -4+-3 these added together give you -7.
so you are left with m^2 +0 -7
which simplifies to m^2 - 7