I guess a mod came to the conclusion that 41 sites are enough to answer your question: "Which Bitcoin Client do you use and why ?"
That can be one of the stupidest reason to lock a thread, because almost every Q asked on BitcoinTalk is answered somewhere on some website.
নির্বোধের জন্যে সময় নষ্ট করে কি লাভ?
Is it the reason? I think you don't have right to use Bengali in Meta which is meant for global discussion = English only. It's my personal opinion though.
May be. But, two answers were in English as well. And I have seen some European native language speakers, e.g. German/Dutch, sometimes communicate among themselves in main forum as well.