One of the best ways to advoid ingury while biking is to
a. bike only during the morning hours
b. constantly switch gears so that you don't add stress to your muscles
c. make sure that positions of the bike seats are appropriate for your hight
d. pedal as quickly as possible when attempting to go uphill

C. Make sure that positions of the seats are appropriate for your height.

Explanation:

The best precautionary step to protect oneself from bike injury is to ensure that the height as well as the positions of the bike seats is appropriate for the riders.

Explanation:

Injuries during riding the vehicles are caused due to failing of following the precautionary steps.

For riding each and every vehicles there are certain precautionary measures which the rides must strictly follow.

For example wearing of helmet, riding the bike with two people, following the correct speed etc must be strictly followed.

In certain cases due to fantancy and interest people forget to chose the bike without thinking that weather they can ride that bike or not or it suits their height etc.

The best step to avoid bike injury is to buy or use such bike which has seats appropriate to the height of the rider.