outfile.txt的内容如下：hellochina下面程序的输出结果是（ ）outfile = open("outfile.txt", "w")outfile.writelines(["hello", " ", "china"])outfile.close()outfile = open("outfile.txt", "a")outfile.writelines(["hello", " ", "china"])outfile.close()infile = open("outfile.txt", "r")print(infile.read())
A. hello china
B. hello chinahello china
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