Definition: In this task, you need to provide the correct option for a given problem from the provided options.
Input: Problem: in a class of boys and girls vikas ' s rank is 9 th and tanvi ' s rank is 17 th . vikas ' s rank among the boys in that class is 4 th from the top and 18 th from the bottom and tanvi ' s rank among the girls is 8 th from top and 21 st from bottom . in the order of rank , how many girls are there between tanvi and vikas ?
Options: a ) 29 , b ) 8 , c ) 2 , d ) 4 , e ) 6
Output:
c