Answer:
Carbon's valence is ±4.
Explanation:
Valency corresponds to the group;
Group 1 has valency +1
Group 2 has valency +2
Group 3 has valency +3
Group 4 has valency ±4
Group 5 has valency -3
Group 6 has valency -2
Group 7 has valency -1
Group 8 has valency 0
The valency refers to how many bonds an atom will make in forming a molecule/compound;
This is also referred to as the combining power of an atom.