To accurately compare the motion during the first 10 minutes to the last 10 minutes, the context is important. Without additional details such as whether he is accelerating, decelerating, changing direction, or maintaining constant speed, we can only generalize.
However, if we assume that the statements presented are indeed correct, the most definitive one would be: He is speeding up during the first 10 minutes and slowing down during the last 10 minutes. This implies a change in acceleration over the two intervals.
So if we take that assumption for comparison, the correct statement from your options would be:
He is speeding up during the first 10 minutes and slowing down during the last 10 minutes.
If you have specific context or numerical data that pertain to speed, acceleration, or direction during those time intervals, please provide that for a more accurate comparison.