The missing reason in the question is option B which is ASA that is ANGLE SIDE ANGLE.
What are congruent triangles?
Triangles are congruent when they have three corresponding sides and exactly the corresponding three angles are equal to other.
What are similar triangles?
If two triangles can be superimposed on each other then it is said to be similar triangles.
How to check similarity between triangles?
Two triangles are said to be similar if two angle and a side, one angle and two sides are equal to other.
If we look at the figure we found that both triangles the marked angles are same for the side and also the angle of G which connects both triangles together.
Hence the correct option for the problem is ASA (Angle Side Angle)
Learn more about congruent triangles at https://brainly.com/question/2938476
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