In an experiment involving an enzyme, the pH is raised from 2 to 11. What will be the most likely effect of this on the reaction?

Raising pH from 2 to 11 means the enzyme is getting an acidic from the basic nature ... The activity of the substance will be most effective if it is working in acidic pH. In that case it activity would have stopped.

If enzyme is in basic nature then its activity will be enhanced to many times.