In this question, we are being asked how many degrees the minute hand of a clock will move in a period of 2 hours and 20 minutes.

Option 1 suggests the minute hand will move 520°. However, since the minute hand completes a full rotation (360 degrees) in 1 hour, in 2 hours and 20 minutes (or 2.33 hours), it should complete more than one rotation. Hence, 520° is less than what it should be.

Option 2 suggests the minute hand will move 320°. This is clearly less than one rotation, which is impossible for a period of 2 hours 20 minutes.

Option 3 suggests the minute hand will move 840°. Given that the minute hand moves 360° per hour, in 2.33 hours it will move approximately 840° (360° * 2.33 = 839.2° which is roughly 840°). Thus, it seems to be the right answer.

Option 4 suggests the minute hand will move 140°, which is impossible, since we are considering a time period of more than 2 hours.

Therefore, the correct answer is Option 3. It`s the only option that aligns with