Answer:
Option C is correct
Conversion factor is used : 60 seconds / 1 minutes
Explanation:
Given: Speed = 20.1 meters per second
To convert this speed in meters per minute.
Conversion Factor is the relationships between units to convert from one unit to another unit.
Use conversion: 1 minute= 60 second
speed =

Now, multiply the speed in meter/seconds with 60 seconds and you will get the speed in meters/minute.
i.e,
speed =

Therefore, the conversion factor is used : 60 seconds / 1 minutes