Question

What is the missing reason???

Answer 1

Given that,

AD is parallel to EC, BD is congruent to BC.

Solution,

Here,

`\angle D=\angle C` = the reason for this is that the two angles are alternate interior angle. So, by alternate interior angle theorem
`\angle D=\angle C`.

As
`\angle ABD=\angle EBC` = due to vertically opposite theorem

It means,

`\triangle ABD \cong \triangle EBC` (angle-side-angle)

Hence, the correct option is (c).