As the event of “Sunny Sports” develops in our country, the government has paid more attention to students’ health and raised “Exercise one-hour a day.小题1:k_________illness away.” So far our school life has 小题2:c____________a lot. Now we have more time to take part in exercise at school. We play basketball, 小题3:f__________, badminton and so on. They make our brains relaxed and our school life more colourful. We have become more 小题4:e__________and our study has improved a lot. It can build up our body and reduce diseases. Let’s小题5:t__________exercise every day!

某单位转让一幢已经使用过的楼房，售价500万元。该楼房原价为600万元，已提折旧400万元。经房地产评估机构评估，该楼重置成本价为800万元，成新度折扣率为五成。转让时缴纳各种税费共27.5万元。该单位应缴纳的土地增值税是( )。

A．25万元

B．24.15万元

C．20万元

D．21.75万元