Doctors and lawyers ______ that advertising will certainly ______ their profession seriously.

Doctors and lawyers that advertising will certainly their profession seriously.

Believe ...... Effect

Contemplate ...... Boost

Argue ...... Effect

None of these

"Believe" fits logically, as doctors/lawyers hold opinions about advertising.

"Effect" (as a verb) means to bring about a change, which aligns with the impact of advertising on their professions.