Final answer:
The surface area of the right cylinder is 90π units².
Step-by-step explanation:
The surface area of a right cylinder can be calculated using the formula:
A = 2πr² + 2πrh
Given that the radius (r) is 3 units and the height (h) is 12 units, we can substitute these values into the formula:
A = 2π(3²) + 2π(3)(12)
A = 2π(9) + 2π(36)
A = 18π + 72π
A = 90π
Therefore, the surface area of the right cylinder is 90π units², which corresponds to option B.