A supercharger is used in the engines of earthmoving machines at higher altitudes because
(a) The ambient atmospheric pressure is less at higher altitudes
(b) Four-cycle engines depend on the suction of the engines for the supply of air
(c) Two-cycle engines are not rugged enough for higher altitude
(d) The ambient temperature is less as the altitude is higher
(a) The ambient atmospheric pressure is less at higher altitudes
(b) Four-cycle engines depend on the suction of the engines for the supply of air
(c) Two-cycle engines are not rugged enough for higher altitude
(d) The ambient temperature is less as the altitude is higher