Two statements are given, followed by four conclusions I, II, III and IV. Assuming these statements to be true, even if they seem to be at variance with commonly known facts, decide which of the given conclusions logically follow(s) from the statements.
Statements:
Some boxes are dolls.
All dolls are pens.
Conclusions:
I. Some boxes are pens.
II. Some pens are boxes.
III. Some pens are dolls.
IV. All pens are dolls.