Suppose we have the following relations:

R S

A B B C

0 1 0 1

1 2 1 2

2 3 2 3

and we take their natural join. Apply the Map function to the tuples of these relations. Then, construct the elements that are input to the Reduce function. Identify which of these elements in the list below. a) (0, (S,1))

b) (1, [(R,0)])

c) (2, [(R,1)])

d) (1, [(R,0), (S,2)])