Exercise 3. Choose the best answer to complete each unfinished sentence, substitutes the underlined part, or has a close meaning to the original one.
On behalf of the referees and athletes, referee Hoang Quoc Vinh and shooter Nguyen Manh Tuong swore to an oath of "_______, Honesty and Fair Play".
A.Performance
B.Delegation
C.Participation
D.Solidarity