Answer:
choice C is correct
Explanation:
The clockwise sequence of vertices MNO is the opposite of the counterclockwise sequence of vertices M'N'O', so it seems some sort of reflection is involved.
Length NO is 3 times length N'O', but length NM is only 7/3 times length N'M', so the figures are not similar. (The ratios of side lengths must be the same for the figures to be similar.)
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Choice D includes only rigid transformations that would ensure congruence. Similar figures may also differ by a dilation factor, so C is the better choice.