Three Statements followed by three Conclusions are given below. You have to take the Statements to be true even if they seem to be at variance with commonly known facts. Read all the Statements and Conclusions and then decide which of the given Conclusions logically follows/follow from the Statements, disregarding the commonly known facts:

Statement-1: Some doctors are researchers.

Statement-2: All researchers are professors.

Statement-3: No professor is a clerk.

Conclusion-I: Some professors are doctors.

Conclusion-II: No doctor is a clerk.

Conclusion-III: Some researchers are not clerks.

Which one of the following is correct?