निम्नलिखित ऊर्जा स्त्रोतों में से कौन सा सर्वोतम पर्यावरण अनुकूल है ? - Which of the following energy sources is the best environment friendly? - NimnLikhit Urja Stroton Me Se Kaun Saa Sarvotam Paryavaran Anukool Hai ? UP GK in hindi, उर्जा संसाधन Van Utpaad question answers in hindi pdf Nabhikiy Vikhandan questions in hindi, Know About Petroleum Utpaad UP GK online test UP GK notes in hindi quiz book Solar Sale