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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Replacement of columnar epithelium in respiratory tract to squamous epithelium is ?
assistant
The correct answer is  Ans. is `c' i.e., Metaplasia Metaplasia Metaplasia is a reversible change in which one differentiated cell type is replaced by another differentiated cell type. Metaplasia represents an adaptive substitution of cells that are sensitive to stress by cell types better able to withstand the adverse environment.