To understand the difference between comp and comp-3 usage, the user needs to know about the different data types in COBOL programming language.
A) Comp is binary usage, while comp-3 indicates packed decimal.
This option is incorrect because comp is not binary usage. Comp is a usage for binary integers and comp-3 is a usage for packed decimal.
B) Comp is a packed decimal, while comp-3 indicates binary usage.
This option is incorrect because it incorrectly states the usages of comp and comp-3. Comp is a usage for binary integers, while comp-3 is a usage for packed decimal.
C) Comp and Comp-3 are packed decimal.
This option is incorrect because comp and comp-3 are not both packed decimal. Comp is a usage for binary integers, while comp-3 is a usage for packed decimal.
D) Comp and Comp-3 are binary usage.
This option is incorrect because comp and comp-3 are not both binary usage. Comp is a usage for binary integers, while comp-3 is a usage for packed decimal.
The Answer is: A. Comp is binary usage, while comp-3 indicates packed decimal.