The figure below shows rectangle abcd with diagonals segment ac and segment db:

jimmy wrote the following proof to show that the diagonals of rectangle abcd are congruent:

jimmy's proof:

statement 1: rectangle abcd is given
statement 2: segment ab ≅ segment dc because opposite sides of a rectangle are congruent
statement 3: angles abc and dcb are both right angles by definition of a rectangle
statement 4: angles abc and dcb are congruent because all right angles are congruent)
statement 5:
statement 6: triangles abc and dcb are congruent by sas
statement 7: segment ac ≅ segment db by cpctc

which statement below completes jimmy's proof?

a. segment ad ≅ segment ad (reflexive property of congruence)
b. segment ad ≅ segment ad (transitive property of congruence)
c. segment bc ≅ segment bc (reflexive property of congruence)
d. segment bc ≅ segment bc (transitive property of congruence)