From the illustration above, we are given that side AD is congruent to side CD. This is shown by the tick marks given. Also, it is given that both triangles share the same side BD. Lastly, it is also shown in the given illustration that angles ADB and CDB are congruent.
The congruent angles given is the included angle such that the postulate should be named, SAS.
The answer to this item is the second choice.
