The correct answer is: B. petrol.
Power alcohol is a mixture of petrol and ethyl alcohol. It is used as a fuel in internal combustion engines. It is a cleaner-burning fuel than petrol, and it produces fewer emissions. It is also less volatile than petrol, which makes it safer to handle.
Diesel is a fuel oil that is used in diesel engines. It is a heavier fuel than petrol, and it has a higher cetane number. Cetane number is a measure of the ignition quality of a fuel. Diesel engines require a fuel with a high cetane number in order to operate properly.
Kerosene is a fuel oil that is used in jet engines. It is a lighter fuel than diesel, and it has a lower cetane number. Kerosene engines require a fuel with a low cetane number in order to operate properly.
Mustard is a condiment that is made from the seeds of the mustard plant. It is a yellow or brown paste that is used to add flavor to food. It is not a fuel.