You are going to open a file in your program. The program is saved in a folder, which has a subfolder called "textFiles."In the textFiles folder is a text file called "books.txt."Which line of code will open books.txt?

The file is inside the program’s textFiles subfolder, so its relative path is "textFiles/books.txt". The open() function takes that path and the mode "r" to open the file for reading, and its result is assigned to fileIn. Therefore, the correct line is `fileIn = open("textFiles/books.txt","r")`.

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