Add or Subtract as Indicated $\frac { 3 } { 8 } - \frac { 1 } { 20 }$

Multiple Choice

Add or subtract as indicated.
- $\frac { 3 } { 8 } - \frac { 1 } { 20 }$

A) $\frac { 1 } { 20 }$
B) $\frac { 13 } { 40 }$
C) $\frac { 13 } { 160 }$
D) $\frac { 7 } { 20 }$