Answer:
0.167
Explanation:
Note that 3/18 reduces to 1/6. 1/6 is a rational number whose decimal equivalent is repeating: 1/6 = 0.166666 ...
It appears that answer choices A and D are identical, as arer B and C. You might want to verify that you've copied down the answer correctly.
Answers A and D (identical) are the best choices here, due to less rounding off.