This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: G.I.T., Subject name: Pathology
50 year old male with Gastroesophageal reflux disease- Diagnosis? 
Select and explain. 
A. Squamous metaplasia, B. Columnar metaplasia, C. Dysplasia, D. Malignancy
B: Columnar metaplasia
Answer: B: Columnar metaplasia 
Explanation: Ans. (b) Columnar metaplasia Histological findings of barrett esophagusMetaplastic columnar epithelium (specialized) with goblet cells is seen adjacent to squamous epithelium of esophagus hence suggestive of columnar metaplasiaLong-segment: Barrett's mucosa extends 3 cm or more. Short-segment: Barrett's mucosa extends less than 3 cm