you have this information about δabc, δdef, and δghi:

ab = gh

bc = ef = hi

m∠b = m∠d

m∠b = m∠h

which triangles must be congruent?

-δabc, δdef, and δghi

-δabc and δdef only

- δabc and δghi only

-none of the triangles

Two triangles are congruent if they have: exactly the same three sides and; exactly the same three angles. the information above is not sufficient for telling there are congruent triagles
so the possible answer is
-none of the triangles