Select the correct statement (s) :

Options

A. (a) An electron near the nucleus is attracted by the nucleus and has a low potential energy
B. (b) According to Bohr's theory, an electron continuously radiate energy if it stays in one orbit
C. (c) Bohr's model could not explain the spectra of multielectron atoms
D. (d) Bohr's model was the first atomic model based on quantisation of energy

Answer

To solve the question, we need to evaluate each statement based on Bohr's model of the atom and identify which ones are correct.

### Step-by-Step Solution:

1. **Understanding Bohr's Model**:
- Bohr's model describes the atom as having a nucleus surrounded by electrons that move in fixed orbits. The electrons are attracted to the positively charged nucleus due to electrostatic forces.

2. **Evaluating Statement A**:
- **Statement**: An electron near the nucleus is attracted by the nucleus and has a lower potential energy.
- **Analysis**: According to the principles of electrostatics, the potential energy (PE) of an electron in the electric field of the nucleus is negative and decreases (becomes more negative) as the electron gets closer to the nucleus. Therefore, this statement is **correct**.

3. **Evaluating Statement B**:
- **Statement**: According to Bohr's theory, an electron continuously radiates energy if it stays in one orbit.
- **Analysis**: This statement is **incorrect**. In Bohr's model, electrons in stable orbits do not radiate energy. If they did, they would lose energy and spiral into the nucleus, which contradicts the stability of atoms.

4. **Evaluating Statement C**:
- **Statement**: Bohr's model could not explain the spectra of multi-electron atoms.
- **Analysis**: This statement is **correct**. Bohr's model is primarily applicable to hydrogen-like atoms (with one electron) and does not adequately explain the spectra of multi-electron atoms.

5. **Evaluating Statement D**:
- **Statement**: Bohr's model was the first atomic model based on the quantization of energy.
- **Analysis**: This statement is **correct**. Bohr introduced the concept of quantized energy levels for electrons in an atom, which was a significant advancement in atomic theory.

### Conclusion:
The correct statements are A, C, and D. Therefore, the final answer is **A, C, D**.