Answer:
Othello has married Desdemona before the play starts, and Iago believes her father would be angry for that reason.
Step-by-step explanation:
"Othello" is a tragic play by William Shakespeare. Iago, who pretends to be loyal to Othello, is actually seeking revenge. He resents Othello for having chosen someone else as his lieutenant, and he also believes Othello might have slept with his wife. Because of that, he makes a point of telling Brabantio, Desdemona's father, about his daughter's eloping to marry Othello. He knows Brabantio will not stand still and simply accept losing his daughter like this.