D. 西瓜内容如下：

西瓜 (watermelon) can have different meanings depending on the context. Here are some possible interpretations of your query:

- 西瓜视频 (Watermelon Video) is a popular video app in China that provides high-quality and diverse content for different audiences. It is a leading platform for mid-length videos that aims to broaden people's horizons and satisfy their curiosity about life[^1^].
- 西瓜 (watermelon) is also a delicious and nutritious fruit that is widely cultivated and consumed around the world. It has a green rind and a red or yellow flesh that contains many seeds. It is rich in water, vitamin C, and antioxidants. It can help lower blood pressure, prevent dehydration, and improve skin health.
- 西瓜 (watermelon) can also be used as a metaphor or a slang term in some contexts. For example, in Chinese, 西瓜皮 (watermelon peel) means something that causes trouble or embarrassment, such as a slip of the tongue or a mistake. In English, watermelon can refer to someone who is green on the outside but red on the inside, meaning they pretend to be environmentally friendly but are actually socialist or communist.