Final answer:
The word that means 'to enlarge or expand' is dilate (option c). Dilate means to make or become larger or wider. It is commonly used in medical contexts, such as dilation of blood vessels or dilation of the pupils.
Step-by-step explanation:
The word that means 'to enlarge or expand' is dilate (option c).
Dilate means to make or become larger or wider. It is commonly used in medical contexts, such as dilation of blood vessels or dilation of the pupils. For example, when someone is in a dark room, their pupils dilate to allow more light in.
The other options, dilute, suppress, and retain, have different meanings and do not convey the idea of enlargement or expansion.