Task: Question Answering
Input (English): Problem: in a group of 150 people , 90 have an age of more 30 years , and the others have an age of less than 20 years . if a person is selected at random from this group , what is the probability the person ' s age is less than 20 ? 
Options: a ) 0.4 , b ) 0.5 , c ) 0.65 , d ) 0.75 , e ) 0.85
Output (English): a