In an internal combustion engine the fuel is burned directly inside the cylinder, so the working gas that drives the piston is created right where the power is produced.

The governing contrast is with external combustion engines, such as steam plants, which must first burn fuel in a separate boiler and raise steam before any power is available.

Because combustion happens immediately once the engine is cranked, an IC engine develops power almost at once and therefore reaches running condition very quickly.

This quick start-up is a genuine advantage of IC engines, so the option describing a slow start-up is the opposite of the truth.

The option saying it starts without a compression process is false — petrol and diesel engines both rely on compressing the charge before ignition.

The option saying it starts without cranking is also false, since the crankshaft must be turned by a starter or manual means to begin the cycle.

Only the quick start-up statement correctly describes an IC engine's start-up advantage.

Hence, the answer is Internal combustion engines have quick start-up time.