Matthew 24:45 is a statement Jesus made in the form of a rhetorical question...he didn't intend to get a reply from his audience. There are many instances in the Bible where Jesus would put a question out to his listeners and his listeners would quickly reply with an answer...Mat 24:45 is different. Jesus was merely creating a dramatic effect or making a point rather than wanting/expecting an answer from someone. Who but a knucklehead in an audience would attempt to reply to a rhetorical question!
The rhetorical question:
"Who then is the faithful and wise servant, whom the master has put in charge of the servants in his household to give them their food at the proper time?"
Whose the knucklehead who raises his hand to answer that rhetorical question?
The Watchtower Bible & Tract Society/Governing Body Of Jehovah's Witnessses.