One of the best ways to avoid injury while biking is to
a. continuously switch gears so that you don't add stress to your muscles.
b. pedal as quickly as possible when attempting to go uphill.
c. make sure that the positions of the bike seat and handles are appropriate for your height.
d. bike only during the morning hours.

One of the best ways to avoid injury while biking is to  make sure that the positions of the bike seat and handles are appropriate for your height.By adjusting that we can avoid falling off from the bike and hitting any objects.Apart from that each rider wants to obey the traffic rules so that accident won't occur.

It’s either a or b hope this

People who utilizes the progression principle will ensure their exercise program increases in frequency, intensity, time, and type. the changes need to happen gradually in order to ensure they make gains in their fitness program. a person who doesn't utilize the progression principle can still gain health benefits from exercising, but will not continue to improve in cardiovascular fitness.