Carbon is able to form large numbers of organic compounds because carbon can

A.form 4 bonds
B.form single, double and triple bonds
C.form chains, rings, spheres and sheets
D.the carbon-carbon bond is very stable
E.all answers are correct

http://www.nyu.edu/pages/mathmol/modules/carbon/carbon1.html

A, B, C, are true. Think about diamond (and All C material) for D. Then think about E.
http://www.nyu.edu/pages/mathmol/modules/carbon/carbon1.html

The correct answer is E. all answers are correct.

Carbon is able to form large numbers of organic compounds because of several reasons:

1. Carbon can form four covalent bonds with other atoms. This means that each carbon atom can form bonds with up to four other atoms, including other carbon atoms. This gives carbon the ability to create complex and diverse molecular structures.

2. Carbon can form single, double, and triple bonds. By varying the number of bonds it forms with other atoms, carbon can create different types of chemical compounds with unique properties. This versatility allows for a wide range of organic compounds to be formed.

3. Carbon can form chains, rings, spheres, and sheets. It has the ability to bond with other carbon atoms to form long chains, which can then be further arranged into rings or spheres. These different arrangements contribute to the variety and complexity of carbon-based compounds.

4. The carbon-carbon bond is very stable. This stability allows carbon to form long and complex chains of atoms without breaking easily. This stability is essential for the formation and maintenance of organic compounds.

In summary, carbon's ability to form multiple bonds and various molecular structures, combined with the stability of the carbon-carbon bond, enables it to create a vast number of organic compounds.