OG详解-OG1 数学1 Q9

Choice B is correct. It’s given that triangle LMN is similar to triangle PQR. Corresponding angles of similar triangles are congruent. Since angle M and angle Q correspond to each other, they must be congruent. Therefore, if the measure of angle M is  53° then the measure of angle Q is also 53°.
Choice A is incorrect and may result from concluding that angle M and angle Q are complementary rather than congruent. Choice C is incorrect and may result from concluding that angle M and angle Q are supplementary rather than congruent. Choice D is incorrect and may result from conceptual or calculation errors.