The right answer is True.
Worldwide acid rain is normally acidic with a pH of 5 to 5.6. This small amount of acid comes mainly from the absorption of natural gaseous CO2 in the air. On the other hand the rains today are ten times more acidic (pH 4.6 to 4.0) than normal mainly because of the addition of sulfur dioxide SO2 and also nitrogen oxides (NOx) in the atmosphere.