Explanation

Explanation:

1. The comparative form of the adjective "fast" is "faster" when comparing two things.

2. In this case, we are comparing the speed of a tiger and an elephant, so the correct form to use is "faster" instead of "fast."

3. The conjunction "than" is used to show the comparison between the speed of the tiger and the elephant.

4. Additionally, "an" is used before both "tiger" and "elephant" as they are singular nouns.