Since q = s * m * ΔT, you can rearrange to solve for s by dividing both sides by m and ΔT, which yields:

s = q / (m * ΔT)

which is the same as q * m^-1 * ΔT^-1 since negative exponents mean something is in the denominator. So your answer is d.

s = q/(m ΔT)