Concept:Othello arrives because an emergency alarm has called him to the scene of a disorderly fight.
Explanation:After Cassio and Montano begin fighting, Roderigo raises a public alarm by ringing a bell.
Othello enters only after this bell is rung.
His first order is: “Silence the dreadful bell, it frights the isle / From her propriety.”
This shows that the ringing of the bell has brought him out to investigate.
He then asks, “What is the matter, masters?” and later, “Who began this?”
Iago’s drunkenness is not the reason, and Othello does not yet know that Cassio has wounded Montano.
The fight is taking place, but it is the bell that actually summons Othello to the scene.
Therefore, the most direct cause is the sounding of the alarm bell.
Answer:B. A bell has been rung