Pepsin is inactivated at pH

Correct! Wrong!

Pepsin is inactivated at pH above 5. Secreted by the chief cells of the stomach lining, Pepsin is an endopeptidase that digest proteins into smaller peptides. Pepsin is work best in acidic environments between pH 1.5 to 2.0 with an optimum temperature between 37 °C and 42 °C.