In computer networking, the commonly used abbreviation ISP stands for which of the following?

Introduction / Context:
When users connect their computers or mobile devices to the internet, they normally purchase access from a company known by the abbreviation ISP. This term appears on bills, router manuals, and support guides. The question tests whether you know the full form of ISP in the context of computer networking and everyday internet access.

Given Data / Assumptions:

• The abbreviation ISP appears in a computer science and networking context.
• The role involves providing connectivity to the wider internet.
• The options mix Internet and Intranet with Service and Systems.

Concept / Approach:
An Internet Service Provider is a company or organisation that supplies access to the internet for homes, businesses, and institutions. They may provide services such as broadband, fibre, mobile data, and domain hosting. The key words are Internet and Service Provider, because the company provides a service, not just systems, and it is specifically related to the public internet, not a local intranet within a single organisation.

Step-by-Step Solution:
Step 1: Identify that the question refers to access to the internet, so the expansion must include the word Internet rather than Intranet. Step 2: Recognise that the company is providing a service to customers, which fits the phrase Service Provider more than Systems Provider. Step 3: Combine these observations to see that Internet Service Provider perfectly describes the role. Step 4: Compare with Intranet based options, which refer to private internal networks and are not the standard use of ISP. Step 5: Conclude that Internet Service Provider is the correct full form of ISP in common networking terminology.

Verification / Alternative check:
Look at any broadband or mobile data bill or advertisement, which will refer to companies as internet service providers. They are responsible for assigning IP addresses, routing traffic, and maintaining connectivity to the global internet. The term intranet is usually reserved for private internal networks inside organisations, and there is no widely used abbreviation such as Intranet Service Provider in standard practice. This confirms the choice of Internet Service Provider.

Why Other Options Are Wrong:
Intranet Service Provider: This is wrong because intranets are internal to organisations and are not normally described using the ISP abbreviation. The common public term refers to internet access, not intranet access.
Internet Systems Provider: This is wrong because systems provider would emphasise supplying hardware or software systems rather than providing a connectivity service. It is not the standard expansion of ISP.
Intranet Systems Provider: This is wrong because it combines intranet and systems, neither of which matches the usual meaning of ISP in networking exams or everyday use.

Common Pitfalls:
Students sometimes confuse Internet and Intranet because the words sound similar. Remember that Internet is the global public network, while an intranet is private and internal. Another pitfall is to overthink the words and choose Systems because it sounds more technical, but the industry always refers to these companies as service providers, since they sell internet connectivity and related services.

Final Answer:
In computer networking, ISP stands for Internet Service Provider.