动物的学习行为是指在____ 的基础上，通过环境因素的作用，由____ 和____ 而获得的行为．

下列关于人体结构层次的描述中，正确的是（  ）

C

     Cultural relics (文物) carry rich history. But sometimes, they seem like something that only older people enjoy. Recently, a CCTV show about cultural relics has taken young people by storm. It's called National Treasure．

     The show has been highly praised on Bilibili.com. This website is believed to be China's biggest pop culture website for young people. So how can a show about relics from hundreds or even thousands of years ago attract so many young viewers?

     The show's 10 episodes (集) show 27 treasures from nine museums across China. Instead of telling the stories and history behind them, the show invites famous actors to act out these stories on stage．

     Actor Wang Kai plays Emperor Qianlong on the show．He meets ancient artists, as well as his father, Emperor Yongzheng, in a dream．They criticize Qianlong's taste in such fancy designs. But Qianlong argues by saying that this kind of design is the best way to show the prosperity of his time.

     This soon became a hot topic online. Screenshots of Wang Kai's performance were made into popular memes. Internet users also compared pictures of vases from the times of Qianlong (1736-1796) and Yongzheng (1678-1735)．

     The stars might be part of the reason that young viewers enjoy the show. But it is still the treasures themselves that are the main focus. “The treasures make me so proud of our country and culture”, internet user “Fengshiyuci” wrote on Sina Weibo. “After watching the show, I want to visit all the museums in China,” wrote by another user with the screen name “Pilipalaxiong”．

    木棉、石栗、椰树、棕榈、凤凰树……这些树木，自然都洋溢着亚热带的情调，并且各自具有独特的风格。但是在和南方居民生活关系密切这一点来说，谁也比不上榕树。一株株古老的、盘根错节、桠杈上垂着一簇簇老人胡须似的“气根”的榕树，遍布在村落周围。在巨大的榕树的树荫下开大会、听报告、乘凉、聊天、午睡、下棋，几乎是任何南方人生活中必曾有过的一课了。

下列没有语病的一句是   (         )