To answer this question, you need to be familiar with the Job Control Language (JCL) used in mainframe systems.
The correct answer is D) 71.
JCL is a scripting language used to control batch processing on IBM mainframe systems. In JCL, each statement or command should be written on a separate line. The maximum length of a single line in JCL is 71 characters.
The correct answer is option D) 71. This option is correct because it represents the maximum length of a single line in JCL.