极限（）。

• A.<img src="https://timg.fentiku.com/javaimportItems/5a0ee0818ee541a6b8e9f3450511d5c6/images/1c6e.png"><br/>
• B.<img src="https://timg.fentiku.com/javaimportItems/5a0ee0818ee541a6b8e9f3450511d5c6/images/252b.png"><br/>
• C.<img src="https://timg.fentiku.com/javaimportItems/5a0ee0818ee541a6b8e9f3450511d5c6/images/2dd4.png"><br/>
• D.<img src="https://timg.fentiku.com/javaimportItems/5a0ee0818ee541a6b8e9f3450511d5c6/images/364a.png"><br/>

正确答案：B