What should you enter at the command prompt to check the tcp wrapper configuration on your system?

The correct answer to the following question will be tcpdchk.

Explanation:

tcpdchk stands for tcp wrapper configuration checker.

It is used to report the problems which will found on your tcp wrapper configuration while surveying and try to fix it where possible.

Type of problems that can reported by the tcpdchk. These are as follows:

Non-existent path names, Unsuitable use of pattern, Unreasonable arguments, etc

Hence, tcpdchk is the correct answer.