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:
I. All markers are pens.
II. No pen is pencil.
III. Some pens are sharpeners.
Conclusions:
I. Some pens are markers.
II. No marker is pencil.
III. No marker is sharpener.

Conclusion: I. Some pens are markers.

The statement, 'All markers are pens.' is given. So the reverse of 'some' relation will be available between them. The given conclusion follows.

Conclusion: II. No marker is pencil.

'No pen is pencil.' is given in the statement and some part of pen is marker. So the given conclusion follows. 

Conclusion: III. No marker is sharpener.

There is not any direct relation between 'marker' and 'sharpener'. So the given coclusion does not follow.