ANSWER
A. 150 units^2
EXPLANATION
The surface area of a cube is calculated using the formula:
[tex]SA=6 {l}^{2} [/tex]
where
[tex]l = 5[/tex]
We substitute the length to obtain:
[tex]SA=6 {l}^{2} [/tex]
[tex]SA=6 \times {5}^{2} [/tex]
[tex]SA=150 \: {units}^{2} [/tex]
