Let U represent the set of people in a certain community who were asked if they subscribe to an information source.

Let D ={ x ∈ U | x subscribes to The Daily Informer }
and
N ={ x ∈ U | x subscribes to News Magazine }

(Assume these sets are not disjoint.) Write the set that represents the set of people surveyed who subscribe to The Daily Informer but not News Magazine.

a) D

b) ( N ∪ D )c

c) N c ∪ D

d) N c ∪ D c

e) N c ∩ D

f) None of the above.