The energy of the electron in the `3d` orbital is less than that in the `4s` orbital in the hydrogen atom

Explanation

To determine whether the statement "The energy of the electron in the 3d orbital is less than that in the 4s orbital in the hydrogen atom" is correct or false, we can analyze the energy levels of these orbitals using the n + l rule.

### Step-by-Step Solution:

1. **Identify the Quantum Numbers**:
- For the **3d orbital**:
- Principal quantum number (n) = 3
- Azimuthal quantum number (l) for d = 2
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