Fill in the Blank with One of the Words or Phrases

Multiple Choice

Fill in the blank with one of the words or phrases listed below.

-If $\mathrm { a } ^ { 2 } = \mathrm { b }$ , then $\mathrm { a } =ــــــــــ$

A) $\frac { - b } { 2 a }$
B) $( 0 , \mathrm { k } )$
C) $( h , 0 )$
D) $\pm \sqrt { b }$