Stock trades are all handled by specialized salespeople called

A e-traders

B. stockbrokers

C. finance traders

D. investment counselors

The answer is

b. stockbrokers

Your answer would be C) finance traders

Stockbrokers (or B) are brokers so you answer can't be stockbrokers

Investment counselors (or D) are people give recommendations about security to their clients

E-traders (or A) are people who specifically trade in the e trade platform; finance traders and also e traders but finance traders can trade on other platforms not only e-trade.