If the intake air temperature of IC engine increases, its efficieney will: (a) increase (b) decrease (c) remain same d) unpredictable (e) depend on other factors.

(b) decrease

Explanation:

If the intake of the sir temperature of the IC engine increases, the efficiency will decrease,

Since,

as the temperature will increase, the density of the air will reduce,

And,

as the density of the air decreases, the expansion ratio will reduce, i. e., The efficiency of the IC engine will decrease.