Zymogen cells and chief cells that secrete

Explanation : 

• The gastric chief cell is a cell that produces pepsinogen and chymosin in the stomach.
• Chief cells, also known as zymogenic cells or peptic cells, are a type of cell that produces a zymogen.
• When pepsinogen comes into touch with acid produced by gastric parietal cells, it is converted into the digesting enzyme pepsin. As a result, pepsinogen is secreted by Zymogen cells and main cells.
• As a result, the appropriate response is 'Pepsinogen.'

Final Answer : 

Option C : Zymogen cells and chief cells that secrete Pepsinogen.