小林编写一段文件读写操作代码，文件如图，代码段如下：

file=open('ceshi.txt','w')

file.write("python is a programming language.")

file.close( )

file=open('ceshi.txt','r')

print(file.read( ))

该代码段运行后，输出的结果为（   ）

A、IA Distributed System Based on Python.

B、python is a programming language.

C、IA Distributed System Based on Python. python is a programming language.

D、程序编译错误，不会输出结果