This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Data Variables, Subject name: Social & Preventive Medicine
A Physician, after examining a group of patients of a certain disease, classifies the condition of each one as 'Normal', 'Mild', Moderate' or Severe'. Which one of the following is the scale of measurement that is being adopted for classification of the disease condition? 
Select and explain. 
A. Nominal, B. Interval, C. Ratio, D. Ordinal
D: Ordinal
Answer: D: Ordinal 
Explanation: Ans. is 'd' i.e. Ordinal Refer to Q. no. 42 of May 2005, & Q. no. 36 of Nov. 2003