SSC JE Mechanical Engineering 27 Sep 2019 Shift 2 Paper

Two Statements are given followed by four conclusions numbered I, II, III and IV. 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:
1) All pens are scales
2) Some Erasers are scales
Conclusions:
I. All pens are erasers
II. All erasers are pens
III. Some scales are erasers
IV. All scales are pens