A9. In a football team, there are 11 players, whose average age is 21 years. Which statement is definitely correct?
(A) The majority of players in the team are 21 years old.
(B) All players are younger than 21 years.
(C) All players together are 242 years old.
(D) At least five players are exactly 21 years old.
(E) The sum of the ages of all players is 231 years.
A9. All players together are $11 \cdot 21=231$ years old.