Task: Question Answering
Input (English): Problem: of the 200 employees at company x , 80 are full - time , and 150 have worked at company x for at least a year . there are 20 employees at company x who aren ’ t full - time and haven ’ t worked at company x for at least a year . how many full - time employees of company x have worked at the company for at least a year ? 
Options: a ) 20 , b ) 30 , c ) 50 , d ) 80 , e ) 100
Output (English): c