The main part of your program has the following line of code. answer = difference(30,5)
Which function finds the difference of 30 and 5 to return 25.

a-def Subtract(numA, numB):
return numB - numA

b-def Subtract(numA, numB):
return numA - numB

c-def subtract(numA, numB):
return numA - numB

d-def subtract(numA, numB):
return numB - numA