Answer:
2 units wide, 8 units long
Explanation:
In this situation, width x length = area. Therefore, the two numbers in the correct answer must correctly multiply to 16.
4 x 2 = 8, so 4 units by 2 units is incorrect.
2 x 6 = 12, so 2 units by 6 units is incorrect.
4 x 3 = 12, so 4 units by 3 units is incorrect.
2 x 8 = 16, so 2 units by 8 units is correct.