It was extremely discouraging to learn that the bank, with whom I have had a savings account for over twenty years, could not open a checking account for me because I did not have proper identification.

a. that the bank, with whom I have had a savings account for over twenty years
b. that the bank, with which I have had a savings account for over twenty years
c. that the bank, with who I have had a savings account for over twenty years
d. that the bank, with that I have had a savings account for over twenty years
e. that the bank, where I have had a savings account for over twenty years

OA B











For D, it says "where I have had a savings account for over twenty years" becomes as adjective phrase, modifying bank, and the commas are no longer needed. Why arent the commas needed?