Answer:
Option D. ET=IT
Step-by-step explanation:
we know that
The Side Angle Side postulate (SAS) states that if two sides and the included angle of one triangle are congruent to two sides and the included angle of another triangle, then these two triangles are congruent
In this problem
the included angle ∠ETK of triangle TEK is congruent with the included angle ∠KTI of triangle TIK
the side KT is a common side both triangles
therefore
ET must be equal to IT to prove that triangles TEK and TIK are congruent by SAS postulate