What is a carriage return?
If you do much programming you will probably have this committed to memory. Mostly because of CR (13), LF(10) (base 10) and the three different ways they are used to represent newline on three popular platforms (which leaves one way to get it wrong for all three). These are control characters and do not represent printable characters. 

CR = Carriage Return

LF = Line Feed

'Denary' is an unusual way, in my experience, to refer to decimal (base 10) numbers. Perhaps the question is translated from another language or the author is being pedantic.