Correct Answer - D
The maximum number of electron in an orbit is `2 n^(2)`. Since `n gt4` is not possible , therefore the maximum number of electron that can be in the first four orbit are
`2 (1)^(2) + 2 (2)^(2) + 2 (3)^(2) + 2 (4) = 2 + 8 + 18 + 32 = 60`
Therefore, possible element are`60`