The best thing to do is figure out what we can deduce to isolate what we can't deduce. The first answer is true because angles 1 and 8 are congruent by the Alternate Exterior Angles Theorem, which states that if two lines are congruent, it's alternate exterior angles are congruent. The second answer is true by the Same-Side Interior Angles Theorem, which states that angles created by a transversal that are both in the interior of the transversal are congruent. The third choice is incorrect, and we know this is true because the previous theorem we used (Same Side Interior Angles) is shown again, but with different angles. Therefore, Choice C is incorrect, and therefore your answer.
(As a side note, Choice D is correct, but a short proof must be written to prove this, as it is not defined by a single postulate or theorem).
