Step 1: Understanding the Concept:
The question asks to identify the features of Internal Communication. Internal communication is the flow of information and ideas within an organization, as opposed to external communication, which is with outside parties.
Step 2: Detailed Explanation:
Let's analyze each statement:
(A) Interaction between employer and employee of same organisation: This is a form of downward or upward communication, which is a core part of internal communication.
(B) Interaction between two employees of same department and same organisation: This is peer-to-peer or horizontal communication within a team or department. This is a classic example of internal communication.
(C) Interaction among several employees of same organization but different departments: This is cross-functional or diagonal communication, essential for collaboration and coordination within the organization. This is also a form of internal communication.
(D) Interaction between employees of different organizations: This is, by definition, external communication. It involves interacting with people outside of one's own company (e.g., vendors, clients, partners).
Step 3: Final Answer:
Statements (A), (B), and (C) all describe communication that occurs *within* the boundaries of a single organization. Statement (D) describes communication that crosses those boundaries. Therefore, the characteristic features of internal communication are (A), (B), and (C).