12. The ability of Carbon to form up to 4 bonds is important to living organisms in that it allows Carbon to A. bond only with Hydrogen and Oxygen.
B. decay into Boron.
C. build quadruple bonds.
D. form rings and chains.

D, form rings and chaines i think

Explanation:

This allows the Carbon to form long chians with elements such as hydrogen and phosphorus, etc, used some info from this site

https://courses.lumenlearning.com/wm-nmbiology1/chapter/carbon-and-carbon-bonding/

if my answer helps please mark as brainliest.

stress fractures occur largely in the feet and legs and are common in sports that require repetitive impact, primarily running/jumping sports such as gymnastics or track and field.

d. planting trees

the trees take in carbon to make oxygen.