Write the Word or Phrase That Best Completes Each Statement $x = \cos 2 t , y = \sin 2 t , 0 \leq t \leq \pi$

Write the word or phrase that best completes each statement or answers the question.
-Which of the following pairs of parametric equations will graph a semicircle?

A) $x = \cos 2 t , y = \sin 2 t , 0 \leq t \leq \pi$
B) $x = \cos t , y = \sin t , 0 \leq t \leq \frac { \pi } { 2 }$
C) $x = \cos \frac { 1 } { 4 } t , y = \sin \frac { 1 } { 4 } t , 0 \leq t \leq 4 \pi$
D) $x = \cos \frac { 1 } { 2 } \mathrm { t } , \mathrm { y } = \sin \frac { 1 } { 2 } \mathrm { t } , 0 \leq \mathrm { t } \leq \pi$