विधाने: एकही शिक्षणतज्ज्ञ, संशोधक नाही.
सर्व संशोधक शिक्षक आहेत.
अनुमाने :
I. एकही शिक्षक, संशोधक नाही
II. एकही शिक्षक, शिक्षणतज्ज्ञ नाही
III. काही संशोधक हे शिक्षक आहेत
IV. काही शिक्षक हे संशोधक आहेत

The correct answer is Option D (Only III and IV true).

Key Points:
• Let us analyze the given statements:
• Statement 1: No Educationist is a Researcher (E ∩ R = ∅).
• Statement 2: All Researchers are Teachers (R ⊆ T).
• Evaluating conclusions:
• Conclusion I: "No teacher is researcher" — False, since all researchers are teachers, researchers form a subset of teachers.
• Conclusion II: "No teacher is educationist" — False, not necessarily true. Teachers outside the researcher circle can overlap with educationists.
• Conclusion III: "Some researchers are teachers" — True, because if all researchers are teachers, then inherently some researchers are teachers.
• Conclusion IV: "Some teachers are researchers" — True, by subalternation/conversion of "All researchers are teachers" (A-type to I-type proposition).
• Thus, only conclusions III and IV are definitively true.
• Key Takeaway: From 'All R are T', both 'Some R are T' and 'Some T are R' necessarily follow.