In computer networking, two devices are considered to be in a network if which of the following conditions is true?

Introduction / Context:
Computer networks allow different devices to communicate and share resources. The key idea of networking is not just that devices exist or run programs, but that they can exchange information. This question asks you to identify the condition that defines when two devices can truly be considered to be in a network with each other. Recognising this helps you focus on communication capabilities rather than incidental similarities between machines.

Given Data / Assumptions:

• We are dealing with two separate devices such as computers, phones or servers.
• Each device may run one or more processes (programs).
• We want to know when these devices are part of a network.
• Options mention running processes, matching IDs and exchange of information.

Concept / Approach:
In networking, the essential characteristic of a network is the ability to communicate. Two devices are said to be connected in a network if there is a path through which they can send and receive data to and from each other. It is irrelevant whether they have processes with the same process ID or even whether both devices are running processes at the same instant; what matters is the potential for one process to exchange information with another. Therefore, the correct condition is that a process on one device can exchange information with a process on the other device, using some communication medium and protocol.

Step-by-Step Solution:

Verification / Alternative check:
Definitions of a computer network typically state that a network is a collection of interconnected devices that can communicate and share resources. Protocols such as TCP/IP, HTTP and FTP are all built around the idea of processes on different hosts exchanging data packets. Nowhere do networking standards require process IDs to match. In fact, identical PIDs often appear on independent systems that are not connected at all. The ability to send and receive data using network interfaces and protocols is the deciding factor. This reinforces that option C captures the correct condition.

Why Other Options Are Wrong:

• A process is running on both devices at the same time: Processes could run on isolated machines with no network between them; the condition is insufficient.
• The process IDs of running processes are the same: PIDs are assigned independently by each operating system and may coincidentally match without any network relation.
• All of the above conditions must be true: Incorrect because the extra conditions are neither necessary nor meaningful for networking.
• Both devices use the same operating system: Devices can be networked even if they use completely different operating systems, as long as they share common protocols.

Common Pitfalls:
Some learners focus too much on details like process IDs or operating systems and forget the fundamental purpose of networking. It is also easy to confuse running in parallel with being connected. Two devices can run similar programs at the same moment but remain completely isolated. Always return to the core networking idea: if data can be exchanged between processes on different devices, then those devices are in a network relationship. That simple test will guide you to the correct answer in many similar questions.

Final Answer:
Two devices are considered to be in a network if a process on one device is able to exchange information with a process on another device.