The fractions \displaystyle\frac19, \frac14 and \displaystyle\frac{1}{18} are to be added. What is their lowest common denominator?

**Answer Choices**

A. 648

B. 162

C. 72

D. 36

E. 18

The fractions \displaystyle\frac19, \frac14 and \displaystyle\frac{1}{18} are to be added. What is their lowest common denominator?

**Answer Choices**

A. 648

B. 162

C. 72

D. 36

E. 18