I need help solving this question.

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Answer: A
Discussion:
Angle LMO = 55 degrees since triangle LMO is isosceles. Since a triangle has 180 degrees, angle LOM = 180 - (55 + 55) = 70 degrees. Therefore angle LNO = 180 - 55 - (70 + 28) = 27 degrees.
It this is not clear, please place the numbers described above into the diagram.
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