According to molecular orbital theory which of the following is correct `:`

Options

A. LUMO level for `C_2` molecule is `sigma_(2p_x)` orbital
B. In `C_2` molecules both the bonds are `pi` bonds
C. In `C_2^(2-)` ion there is one `sigma` and two `pi` bonds
D. All the above are correct

Explanation

To solve the question regarding molecular orbital theory and the C2 molecule, we will go through the following steps:

### Step 1: Draw the Molecular Orbital Diagram for C2
1. The molecular orbital diagram for C2 consists of the following orbitals:
- σ(1s)
- σ*(1s)
- σ(2s)
- σ*(2s)
- π(2p_y)
- π(2p_z)
- σ(2p_x)
- π*(2p_y)
- π*(2p_z)
- σ*(2p_x)