Final answer:
The common ratio for the given sequence is 1.5.
Step-by-step explanation:
To find the common ratio in a sequence, we need to determine the ratio between each term and the previous term. In this case, we can see that each term is obtained by multiplying the previous term by a certain value.
8 x 1.5 = 12
12 x 1.5 = 18
18 x 1.5 = 27
Therefore, the common ratio for this sequence is 1.5 (option D).