Uniform Resource Locator (URL):

The Uniform Resource Locator also a type of Uniform Resource Indicator, because, it represents the network location of resources like web pages, graphic files, mp3 files, and so on.

• An URL contains:
  • A protocol.
  • Web server name or subdomain.
  • Domain name.
  • Location of the file.

Given that,

“http://www.google.com”

Explanation:

Here,

• http – HTTP protocol.
• www – Web server name or subdomain.
• google.com – domain name.

A domain name can be categorized into two level, they are top-level domain and second-level domain.

• The top-level domain is the extension of domain name.
  • That is, “google.com” is a domain name.
  • Here, “.com” is the extension of domain name; so, “.com” is considered as top-level domain.
• The second-level domain is before to the top-level domain and it is the name of website.
  • That is, “google.com” is a domain name.
  • Here, “google” is the name of the website; so, “google” is considered as second-level domain.

Therefore, “.com” will be the top-level domain name.

Explanation for incorrect options:

“http”:

“http” is considered as the protocol and it is not a domain name.

Hence, the option “A” is wrong.

“google”:

In “google.com”, “.com” is considered as the top level domain whereas “google” is considered as the second-level domain name.

Hence, the option “C” is wrong.

“WWW”:

The “www” is considered as a web server name or host and it is not a domain name.

Hence, the option “D” is wrong.