Three statements are given, followed by three conclusions numbered I, II and III. Assuming the statements to be true, even if they seem to be at variance with commonly known facts, decide which of the conclusions logically follow(s) from the statements.

Statements:

No pen is a box.

Some pens are chalks.

All chalks are erasers.

Conclusions:

I. Some erasers are pens.

II. Some chalks are not boxes.

III. Some boxes are not erasers.