Final answer:
In the quoted passage, Scarus is speaking about Antony's action of leaving the battle to follow Cleopatra, which was considered disgraceful. The context is related to the Battle of Actium in classical literature and Roman history.
Step-by-step explanation:
The passage quoted refers to a scene from classical literature where Scarus comments on Antony's actions during a critical moment in battle. Antony, a powerful leader and once a Roman triumvir, chose to abandon the fight and follow Cleopatra instead. This decision was seen as shameful by his peers and is highlighted by the analogy of a doting mallard abandoning a fight to pursue its mate. The historical context comes from the Roman civil wars, notably the events leading up to and following the Battle of Actium, which was a decisive confrontation that led to the downfall of both Antony and Cleopatra and the rise of Octavian, later known as Augustus, the first Roman Emperor. The answer to the question, which asks for the identification of the subject speaking in the given line, is A) Scarus.