Select correct statement about `I` effect?

Options

A. `I` effect transfers electrons from one carbon atom to another.
B. `I` effect is the polarisation of `sigma` bond electrons.
C. `I` effect creates net charge in the molecule.
D. `I` effect is distance independent.

Explanation

To determine the correct statement about the inductive effect (I effect), we need to analyze the characteristics of this effect step by step.

### Step-by-Step Solution:

1. **Understanding Inductive Effect**: The inductive effect refers to the permanent polarization of a bond due to the electronegativity difference between atoms. In a covalent bond, if one atom is more electronegative than the other, it will attract the shared electrons more strongly.

**Hint**: Remember that electronegativity is the ability of an atom to attract electrons in a bond.

2. **Electron Transfer**: The statement mentions that the I effect transfers electrons from one atom to another. However, the inductive effect does not involve the complete transfer of electrons; instead, it involves the polarization of the electron density towards the more electronegative atom.

**Hint**: Focus on the concept of electron sharing versus electron transfer.

3. **Polarization of Sigma Electrons**: In the case of a bond between carbon and a more electronegative atom (like fluorine), the electron density is pulled towards the electronegative atom, creating a partial negative charge on that atom and a partial positive charge on the less electronegative atom.

**Hint**: Think about how the bond behaves when different electronegativities are involved.

4. **Net Charge Creation**: The statement that the I effect creates a net charge in the molecule is incorrect. The inductive effect results in partial charges, not full charges. Thus, while there are partial charges, there is no overall net charge created in the molecule.

**Hint**: Distinguish between partial charges and net charges.

5. **Distance Dependence**: The inductive effect is distance-dependent. The influence of an electronegative atom decreases with increasing distance from the atom. As you move further away from the electron-withdrawing group, the effect diminishes.

**Hint**: Consider how the strength of an effect changes with distance.

6. **Conclusion**: Based on the analysis, we find that the correct statement about the inductive effect is that it involves the polarization of sigma bond electrons due to the difference in electronegativity, and it does not create a net charge in the molecule nor is it distance independent.

### Final Answer:
The correct statement about the I effect is that it involves the polarization of sigma bond electrons due to electronegativity differences (this corresponds to option B in the original question).