Final answer:
The missing statement and reason in step 2 of a geometric proof involving a parallelogram are most likely 'ab ≅ cd, bc ≅ ad' for the statement and 'given' for the reason, indicating that opposite sides of a parallelogram are congruent by definition.
Step-by-step explanation:
To determine the missing statement and reason in step 2 of the proof, we must examine the options provided and consider the properties of geometric figures involved. In a parallelogram, opposite sides are congruent and opposite angles are congruent, and the diagonals bisect each other. According to the given options:
Option (a) is not sufficient as it simply states that sides are parallel, which is not a congruence statement.
Option (b) directly states that sides are congruent, which is a property of a parallelogram and follows from the information 'given'.
Option (c) assumes congruence of triangles which cannot be concluded directly without further proof.
Option (d) involves corresponding angles and would be correct if the lines were stated to be cut by a transversal, which is not specified here.
Option (e) appeals to alternate interior angles, which would imply parallelism but not congruence of sides or angles on its own.
The correct answer, given the typical properties of a parallelogram and the information commonly provided in geometry problems, is most likely option (b) with the corresponding statement: ab ≅ cd, bc ≅ ad and the reason: given.