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: Surgery
Non progressive contraction of esophagus are 
Select and explain. 
A. Primary, B. Secondary, C. Teiary, D. Quaternary
C: Teiary
Answer: C: Teiary 
Explanation: Three types of contractions in the oesophagus, they are *primary -progressive, triggered by swallowing *secondary-progressive,generated by distension,or irritation *teiary -non-progressive Ref: SRB&;s manual of surgery,5th ed, pg no 788