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

Input: Consider Input: Problem: the present ratio of students to teachers at a certain school is 30 to 1 . if the student enrollment were to increase by 50 students and the number of teachers were to increase by 5 , the ratio of students to teachers would then be 25 to 1 . what is the present number of teachers ? 
Options: a ) 5 , b ) 8 , c ) 10 , d ) 12 , e ) 15

Output: e


Input: Consider Input: Problem: what is the units digit of 26 ! + 50 ! + 4 ! + 4 ! ? 
Options: a ) 8 , b ) 6 , c ) 4 , d ) 2 , e ) 0

Output: a


Input: Consider Input: Problem: in a group of 100 people , 55 have visited iceland and 43 have visited norway . if 61 people have visited both iceland and norway , how many people have visited neither country ? 
Options: a ) 60 , b ) 61 , c ) 62 , d ) 63 , e ) 64


Output: d