For a molecule to exhibit dipole-dipole interactions, it must

(a) have a temporary dipole moment.
(b) have a hydrogen bound to an oxygen, nitrogen, or fluorine.
(c) have a permanent dipole moment.
(d) be an ion.
(e) have 3 or more atoms.

(Correct option is C) Have a permanent dipole moment.

Explanation:

Dipole-dipole interaction is a type of intramolecular interaction between two molecules. They are known as the electrostatics interaction which are present between the permanent dipoles of different molecules. These interactions are helping in to line up the molecules to increase the interaction.

Example of this interaction is: A water molecule contains a large permanent dipole moment. The positive and negative charge on water are not centered at a same point, and it's behave like an opposite, and few charges separated with the help of small distances. This moment of water gives many properties to water, and it's high surface tension.

the ratio of the conjugate base to the acid required to attain the desired ph.