Step 1: Understanding communication barriers.
Common communication barriers include factors that hinder the effective exchange of information between people. These barriers can be psychological, physical, cultural, or organizational.
Step 2: Analyzing the options.
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(A) Linguistic barrier: Incorrect. Linguistic barriers occur when language differences prevent effective communication, making it a common communication barrier.
(B) Interpersonal barrier: Incorrect. Interpersonal barriers arise due to personal conflicts, misunderstandings, or emotional factors, which can obstruct communication.
(C) Financial barrier: Correct. While financial issues can affect an organization or individual, they are not considered a typical communication barrier. Communication barriers are more related to psychological, cultural, or linguistic factors rather than financial.
(D) Organizational barrier: Incorrect. Organizational barriers arise from the structure, policies, or environment of an organization that can hinder communication.
Step 3: Conclusion.
Therefore, the correct answer is (C) Financial barrier, as it is not a common communication barrier in the context of communication theory.
Final Answer: Financial barrier.