In this task, you need to answer the given multiple-choice question on the general math. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Ex Input:
Problem: find a sum for 1 st 7 prime number ' s ? 
Options: a ) 25 , b ) 28 , c ) 58 , d ) 34 , e ) 36

Ex Output:
c


Ex Input:
Problem: a “ palindromic integer ” is an integer that remains the same when its digits are reversed . so , for example , 43334 and 516615 are both examples of palindromic integers . how many 6 - digit palindromic integers are both even and greater than 500000 ? 
Options: a ) 160 , b ) 200 , c ) 240 , d ) 300 , e ) 480

Ex Output:
b


Ex Input:
Problem: if a - b = 8 and a ^ 2 + b ^ 2 = 164 , find the value of ab 
Options: a ) 10 , b ) 12 , c ) 50 , d ) 18 , e ) 19

Ex Output:

c