A reflexive pronoun is a pronoun that ends in -self or -selves. Look at sentence #4: The kids really enjoyed THEMSELVES. The capitalized word ends in -selves.
Answer: The kids really enjoyed themselves.
Plot - is the sequence of events
Who or Whom Did You See? Even though you often hear who did you see in everyday conversations, the most grammatically correct answer is whom did you see. Whom refers to the object of the preposition or verb in a sentence.