Can Someone help me with this i dont understand

In this right triangle  you know an angle and the adjacent leg, and need to find the opposite leg.

the formula that relates those three variables is:

tan(40°) = opposite leg / adjacent leg = height / 2 m

or, which is equivalent,  cot (40°) = adjacent leg / opposite leg = 2m / height

=> height = 2m / cot (40°).
which is the option c of the list.