The answer is D. 24.
To get to the answer, all you needed to do was multiply both sides of the equation with the denominator of the ratio with the unknown value to isolate the missing value on one side of the equation. After that all you need to do is divide.
[tex] 54 * \frac{4}{9} = \frac{m}{54}*54[/tex]
Cancel out the 54 on the right side and do the operation asked on the left side. [tex] \frac{216}{9} =m \\ 24=m[/tex]