Answer:
The first option
Step-by-step explanation:
Carbon is a p-block element. It is the 6th element on the periodic table and therefore it has 6 electrons.
The sub-level notation is given as:
1s² 2s² 2p²
The s-sublevel can only accommodate two maximum electrons because it has one orbital. This is why both 1s and 2s contains just two electrons each. When both sub-levels are filled, we have just 2 remaining electrons to fill the p-sublevel.
The p-sublevel contains 3 orbitals and can accommodate a maximum of 6 electrons. But we have just 2 electrons. According to Hund's rule of maximum mulitiplicity, electrons will go into degenerate orbitals singly before paring up. Therefore, the first two orbitals in p-sublevel will receive an electron each.
This is why the first model fits.