Write the Ratio 12 Feet to 21 Yards as a Fraction

Multiple Choice

Write the ratio 12 feet to 21 yards as a fraction in simplest form. ( Hint: 3 feet = 1 yard.)

A) $\frac { 4 } { 21 }$
B) $\frac { 21 } { 4 }$
C) $21$
D) $\frac { 1 } { 4 }$
E) $4$