TMUA-P2-PRF1-003 — Paper P2 · Direct proof · Level 2

Options

1. A
   A counterexample with $a = 2$, $b = 4$, $c = 8$ is still needed.
2. B
   This proves the converse instead.
3. C
   Since $c$ is larger than $a$, $a \mid c$ follows.
4. D
   Since $st$ is an integer, $c$ is $a$ times an integer, which is exactly $a \mid c$.
5. E
   It only shows $a \mid b$, so nothing is proved.

Letters only — the answer key is hidden. Work it out, then check the solution below.

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