श्वेत वामन
General competitive examinations frequently test candidates on Current Affairs topics. Questions like "बहुत छोटे तारे जिनका व्यास सूर्य के व्यास का 1/50 ..." are designed to verify factual recall and general awareness. Regular practice on similar MCQs ensures a higher accuracy rate. The correct option here is श्वेत वामन.