We need to translate Chinese title "这网站是被 dns 污染了？" into Japanese. Keep proper nouns unchanged; here "dns" is a technical term, keep as "DNS". The sentence means "Is this website DNS polluted?" In Japanese, could be "このサイトはDNS汚染されているのですか？" or "このサイトはDNS汚染ですか？". Keep similar length. Use "DNS" capitalized. So translation: "このサイトはDNS汚染ですか？". Probably good.このサイトはDNS汚染ですか？