Answer Please ! Choose The Correct Reason

{Answer Boxes are similar to all questions :
A: Base angles of an isosceles triangle are congruent
B: Given
C: Def. of an isosceles triangle
D: AA Similarity Theorem
E: Substitution property}

(Question 1 )
Reason 1

(Question2)
Reason 2 < type you’re answer From Answer Boxes>

(Question 3)
Reason 3

(Question 4)
Reason 4

(Question 5)
Reason 5

(Question 6)
Reason 6