Consider the following program where the function, say$\_$motto, is defined but lacks a return statement.

def say$\_$motto $()$:

print $(\text{'}$Service is Sovereignty'$)$

x $=$ say$\_$motto $()$

What is the value of x after the program runs?

A$)0$

B$)$None

C$)$ the program will not run because of an error

D$)"$