Which one of the following methods is not commonly used to obscure a URL?

Question

Which one of the following methods is  not  commonly used to obscure a URL?

Accepted Answer

Incrementing memory buffers through software
modifications

Answer

Expressing the domain name as dotted decimal IP
address in different formats, such as hexadecimal, octal, or double word
(dword)

Answer

Adding irrelevant text after  http://
 and before the  @  symbol

Answer

Representing characters in the URL in hexadecimal
format

Crowdly