The figure below shows rectangle ABCD with diagonals segment AC and segment DB: A rectangle ABCD is shown with diagonals AC and BD.

Anastasia wrote the following proof to show that the diagonals of rectangle ABCD are congruent:

Anastasia's proof:
Statement 1: Rectangle ABCD is given
Statement 2: segment AB ≅ segment DC because opposite sides of a rectangle are congruent
Statement 3: segment AD ≅ segment AD by the reflexive property of congruence
Statement 4:
Statement 5: Angles BAD and ADC are congruent because all right angles are congruent
Statement 6: Triangles BAD and CDA are congruent by SAS
Statement 7: segment AC ≅ segment DB by CPCTC

Which statement below completes Anastasia's proof?

A) Angles BAD and ADC are 90 degrees (perpendicular lines create 90-degree angles)
B) Angles BAD and ABC are 90 degrees (perpendicular lines create 90-degree angles)
C) Angles BAD and ADC are both right angles (definition of a rectangle)
D) Angles BAD and ABC are both right angles (definition of a rectangle)