Answer:
Option A.
Explanation:
Consider below figure attached with this question
Given information: GI = 20 and H = 100°
GHIJ is a rhombus, so all sides are equal.

Since GH=HI, so

Let,

The sum of all interior angles of a triangle is 180 degree.



In a triangle smaller angle have smaller opposite side and greater angle have larger opposite side.




The value of HI is less than 20.
Therefore, the correct option is A.