We will set off with a petrol engine...

We will set off with a petrol engine...
A)We will wait a few seconds.
B)We will wait 10 minutes.
C)Immediately after starting the engine.Correct
In modern vehicles it is not necessary to press the accelerator to start the engine.
In petrol engines, we will set off immediately after starting the engine, thus avoiding fuel consumption at idle (the minimum engine speed required to keep the engine running while not accelerating).
In diesel engines it is advisable to wait a few seconds before setting off so that lubrication is adequate.