D'B' + C'B' + D'A + D'C

which Wolfram Alpha, search: "DNF (~D && ~B) || (~C && ~B) || (~D && A) || (~D && C)", is telling me is equivalent to:

C'B' + D'A + D'C

which is the same except without the D'B' term. How can I derive the second (smaller) one from the first?

Thanks!