In file processing, which of the following behavior is the result of the $"$w$"$ mode?

a$.$ A new file will be created each time when the code runs. The old file will be deleted.

b$.$ When the code runs, a new file will be created if it doesn't exist. If the file exists, the code will append contents to the file.

c$.$ When the code runs, a new file will be created if it doesn't exist. If the file exists, the code will generate an error.

d$.$ When the code runs, a new file will be created if it doesn't exist. If the file exists, the code will wipe out old contents and write new contents in the file.