Which of the following is not an example of an externality?

a. acidic by-products of fossil fuel combustion that produce acid rain.
b. carbon dioxide from energy generation that adds to the worldwide, long-term greenhouse effect.
c. a defective part that causes an automobile to break down three months after purchase.
d. heat from a factory that makes the neighboring tomato patches more productive.

option A

Explanation:

because acid comes from preparation of fossil fuel

vanderwaal's forces of attraction are the electrostatic intermolecular forces that exist in a molecule due to the temporary or permanent dipoles that are developed in a molecule. in , the major intermolecular forces are dipole-dipole interactions as the molecule is polar (bent structure). so the vanderwaal's forces of interaction in between molecules are the permanent dipole-dipole interactions that develop due to the dipole that exists in between the polar h - s bond. the positively charged hydrogen atom is attracted towards the negative end of the dipole that is sulfur of the adjacent molecule. therefore, these forces of attraction are relatively stronger than that of london dispersion forces that exist in non polar molecules.