What statement is true concerning viscosity index as it applies to lubricating oils?

Correct Answer: Option B — An oil with a high viscosity index would have a relatively low rate of change of viscosity as the temperature changes.

Viscosity Index (VI) is an empirical measure of an oil's resistance to viscosity changes as temperature fluctuates. A high VI indicates that the oil maintains a more stable viscosity across a wide temperature range, ensuring consistent lubrication performance and protection for critical engine components during thermal cycling.