`A`, `B` are `C` three sets and `A \cup B \cup C = S` (`S` = universal set). Then `{(A - B) \cup (B - C) \cup (C - A)}^c` equals to the set --
(a) `A \cup B \cup C`, (b) `A \cup (B \cap C)`, (c) `A \cap B \cap C`, (d) `A \cap (B \cup C)`