In this task, you need to provide the correct option for a given problem from the provided options.

Problem: find the number of different prime factors of 441 
Options: a ) 4 , b ) 2 , c ) 3 , d ) 5 , e ) 6
b

Problem: in a group of 28 junior high school students , 5 take french , 10 take spanish , and 4 take both languages . the students taking both french and spanish are not counted with the 7 taking french or the 10 taking spanish . how many students are not taking either french or spanish ? 
Options: a ) 7 , b ) 13 , c ) 9 , d ) 12 , e ) 10
b

Problem: the ratio by weight , measured in pounds , of books to clothes to electronics in a suitcase initially stands at 5 : 4 : 2 . someone removes 7 pounds of clothing from the suitcase , thereby doubling the ratio of books to clothes . how many pounds do the electronics in the suitcase weigh ? 
Options: a ) 6 , b ) 7 , c ) 8 , d ) 9 , e ) 10

b