If the same brand of oil is not available for replenishment, Synthetic Oil Type II may be added provided the total quantity added does not exceed

• A. Two quarts per engine in any 400 hour period
• B. One quart per engine in any 100 hour period
• C. Three quarts per engine in any 200 hour period
• D. Four quarts per engine in any 500 hour period

Answer: (A)

When you can’t get the same brand of oil, you may substitute Synthetic Oil Type II, but you must stay within a strict replenishment limit to protect the engine’s oil balance. The rule is two quarts per engine in any 400-hour period. This per-engine cap ensures you don’t significantly change oil viscosity or additive concentrations while still allowing a temporary top-up between full oil changes.

So, you can add up to two quarts to each engine over any 400-hour window, not more. The other options either propose more or less oil and/or a different time frame that would violate this 400-hour limit.