Ответ:

Comparisons using “than” take the comparative form; comparisons with “the … in the world” or “the … questions” take the superlative form. “Amazing” forms its superlative with “most”; “biggest” cannot modify “cake” in the sentence as printed.

  1. This is the nicest party in my life.
  2. The jokes and games are funnier than last year.
  3. It is the most amazing cake in the world.
  4. She always answers the most difficult questions!
  5. You are the best!