Answer:
S = {(3,p), (3,0), (4,q), (1,4)} is a set of ordered pairs, where the first element of each ordered pair is an integer and the second element is a variable. The set consists of four ordered pairs:
(3,p): The first element is 3 and the second element is p.
(3,0): The first element is 3 and the second element is 0.
(4,q): The first element is 4 and the second element is q.
(1,4): The first element is 1 and the second element is 4.