Which of the following best defines the inductive effect?

The inductive effect refers specifically to the transmission of charge through a chain of atoms in a molecule, which occurs most notably via sigma bonds. In this context, the release of electrons across a sigma bond indicates how certain substituents can influence the distribution of electron density throughout the entire molecule. This can alter properties such as acidity, basicity, and reactivity of the compounds involved.

Substituents that are electron-withdrawing can lead to a decrease in electron density, while electron-donating groups can increase electron density, affecting the overall stability and reactivity of the molecule. This transmission of electron density via sigma bonds is a fundamental concept in understanding how molecular structure influences chemical behavior.

The sharing of electrons in a covalent bond, while related to molecular interaction, does not specifically capture the essence of the inductive effect as it does not highlight the transfer of charge along a chain of atoms. Similarly, the attraction between opposite charges and the repulsion between like charges describe fundamental interactions of electrostatics, rather than the specific mechanism of charge displacement through sigma bonds that characterizes the inductive effect.