QUICK! 30 POINTS! Clara's proof

For triangles AOB and COD, angle 1 is equal to angle 2, as they are vertical angles.
AO = OC and BO = OD because it is given that diagonals bisect each other.
The triangles AOB and COD are congruent by SAS postulate.
Similarly, triangles AOD and COB are congruent.
By , angle ABD is equal to angle CDB and angle ADB is equal to angle CBD.
As the alternate interior angles are congruent, the opposite sides of quadrilateral ABCD are parallel.
Therefore, ABCD is a parallelogram.

Which is the missing phrase in Clara's proof?
CPCTC
property of parallelograms
transitive property
vertical angles theorem

1.3.25 question suppose 40​% of all voters voted for a particular candidate. to simulate exit polls regarding whether or not voters voted for this​ candidate, five random samples of size 1010 and five random samples of size 10001000 have been generated using technology using a population proportion of 0.400.40​, with the accompanying results. complete parts a through c below. click the icon to view the simulation results. a. observe how the sample proportions of successes vary around 0.400.40. simulation compared to sample prop simulation compared to sample prop 1 ▾ 6 ▾ greater than 0.40 less than 0.40 equal to 0.40 2 ▾ less than 0.40 greater than 0.40 equal to 0.40 7 ▾ greater than 0.40 less than 0.40 equal to 0.40 3 ▾ greater than 0.40 less than 0.40 equal to 0.40 8 ▾ equal to 0.40 greater than 0.40 less than 0.40 4 ▾ greater than 0.40 equal to 0.40 less than 0.40 9 ▾ less than 0.40 greater than 0.40 equal to 0.40 5 ▾ equal to 0.40 less than 0.40 greater than 0.40 10 ▾ equal to 0.40 greater than 0.40 less than 0.40 click to select your answer(s) and then click check answer. 2 parts remaining clear all check answer