Explain, explained, explaining, explanation, explanatory a) the package includes an booklet b) the instructions are very clear and do not require any further c) it will only take a couple of minutes to how the program works. d) if you are new to this system, almost everything will have to be

A) The package includes an _explanatory_ booklet 
b) the instructions are very clear and do not require any further __explanation_.
c) it will only take a couple of minutes to _explain_ how the program works. 
d) if you are new to this system, almost everything will have to be explained.

A)explanatory
b)explanation
c)explain
d)explained