In each of the following questions below are given four statements followed by four conclusions numbered I, II, III and IV. You have to assume everything in the statements to be true even, if they seem to be at variance with commonly known facts and then decide which of the four given conclusions logically follows from the statements, disregarding commonly known facts and select the appropriate answer.
All documents are files.
Some files are papers.
All papers are certificates.
No certificate is a manuscript.
I. At least some documents are papers.
II. No manuscript is a document.
III. At least some certificates are files.
IV. No paper is a document.