context: China is a country where 70% of the population is engaged in agriculture. For this reason, the local administration is divided into four vertical structures. The top floor is called the first-level administrative district, and the vast area of ​​the People's Republic of China is horizontally divided into 23 provinces, 5 boroughs and 4 direct districts. The Special Administrative Region is not strictly a first-class administrative district, but it is treated substantially the same.
question: How many surnames are there in China?
answers.text: 23