If x=−a^4, which of the following must be true?
I. x is negative.
II.If a is negative then x is negative.
III. a is non-negative.
Choose the correct answer:
A) I and II only	B) I only	C) II only	D) III only	E) II and III only
I. x is negative --&gt; not necessarily true   II. x is non-negative. m can take ANY value: positive, negative, zero. We don't have any restrictions on its value;   III. If a is negative then x is negative.   Answer: II only (II only).
<result>C</result>
If x=−a^4, which of the following must be true?
I. x is negative.
II.If a is negative then x is negative.
III. a is non-negative.