The correct answer is A. 10 kg/cm2 of FP pressure and 5 kg/cm2 of BP pressure in the engine.
The FP pressure is the fuel pressure, and the BP pressure is the brake pressure. The FP pressure must be at least 10 kg/cm2 to ensure that the engine has enough fuel to operate properly. The BP pressure must be at least 5 kg/cm2 to ensure that the brakes are able to stop the train safely.
The other options are incorrect because they do not meet the minimum requirements for FP and BP pressure. Option B, 08 kg/cm2 of FP pressure, is not high enough to ensure that the engine has enough fuel to operate properly. Option C, 06 kg/cm2 of BP pressure, is not high enough to ensure that the brakes are able to stop the train safely. Option D, 04 kg/cm2 of FP pressure and BP pressure, is not high enough to meet the minimum requirements for either FP or BP pressure.