Concept:The phrase "running battle" means a continuing or repeated disagreement, not a physical fight.Explanation:The word "running" here suggests something lasting or ongoing over time.A "battle" is used metaphorically for an argument or dispute.Thus, the proprietor and accountant have had many arguments about the financial report.Option A is too literal.Options C and D do not match the meaning of the phrase.Answer:B. a series of arguments on the report