Final answer:
The correct answer to the boating safety question is 'Stern (back)', indicating that it is unsafe for passengers to ride on the front (bow) or the back (stern) of a boat.
Step-by-step explanation:
The question pertains to boating safety, specifically the appropriate places for passengers to be located while a boat is in motion. When talking about the various parts of a boat, the term bow refers to the front of the vessel. The options given for the second part of the phrase 'Allowing people to ride on the bow (front) or ___ is not ok?' are: 1) Stern (back), 2) Middle, 3) Port (left), and 4) Starboard (right). The correct answer to fill the blank is '1) Stern (back)' because it is unsafe for passengers to ride on the front (bow) or the back (stern) of the boat where they may easily fall overboard or be injured due to the boat's movement, especially during acceleration or in rough waters.