Answer: Choice C
the segment DE is perpendicular to segment AC
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Explanation:
The tiny square marker indicates we have a 90 degree angle, which in turn means the two segments DE and AC are perpendicular.
Furthermore, DE is a perpendicular bisector of AC because AC is broken into two equal pieces (AE and EC). The term "bisect" means "split in equal halves". We know that AE = EC due to the small tickmarks on each mentioned segment.
Choice B states "AC is a perpendicular bisector". This is incorrect because AC does not split any segments into two equal pieces. If choice B said "DE is a perpendicular bisector", then it would be correct.
