Answer: AAS
Explanation:
Lets call the intersection point between AC and DE F.
I think he meant the two triangles AFE and DFC.
We know angle A is congruent to angle D.
We also know AE is congruent to DC.
There is also a hidden piece of evidence which is AFE is congruent to DFC due to vertical angles.
We know two angles and 1 side, so we can use AAS to figure out that the two smaller triangles are congruent.