Task: Question Answering
Input (English): Problem: of the 600 residents of clermontville , 35 % watch the television show island survival , 40 % watch lovelost lawyers and 50 % watch medical emergency . if all residents watch at least one of these 3 shows and 18 % watch exactly 2 of these shows , then how many clermontville residents c watch all of the shows ? 
Options: a ) 150 , b ) 108 , c ) 42 , d ) 21 , e ) - 21
Output (English): d