Final answer:
The complement of the angle (90°–a) is a° since the definition of a complement is an angle that adds up to 90° when combined with the given angle.
Step-by-step explanation:
The question asks to find the complement of an angle expressed as (90°–a). In mathematics, the complement of an angle is what, when added to the angle, results in a total of 90 degrees. To find the complement of (90°–a), we add it to another angle b such that (90°–a) + b = 90°. The complement of an angle is the angle that, when added to the given angle, equals 90°. In this case, the given angle is (90°–a).Simplifying this, we get b = 90° - (90°–a) = a. Thus, the complement of (90°–a) is a°, which corresponds to option a).