Given the following code for determining if a person has paid enough to go on a tramp:

if payment >= 50:
    payment_is_sufficient = True
else:
    payment_is_sufficient = False
if payment_is_sufficient and (not payment_is_sufficient):
    go_on_tramp()

Which of the following payments will ensure that the function go_on_tramp, assumed to be defined elsewhere, gets called?