Which biological molecules can be separated using polyacrylamide gel electrophoresis (PAGE)?

Polyacrylamide gel electrophoresis (PAGE) is a powerful technique used primarily for separating proteins based on their molecular weight. The key to this method lies in the properties of the polyacrylamide gel, which create a matrix through which proteins can migrate at different rates when an electric field is applied. Smaller proteins typically move more quickly through the gel than larger ones, allowing researchers to resolve a wide range of protein sizes and to analyze their relative abundances.

While PAGE is specially designed for proteins, it can also be adapted for nucleic acids, such as DNA and RNA, but the primary use in many applications is for proteins. Other types of biomolecules, such as carbohydrates and lipids, do not migrate effectively through the polyacrylamide gel for the purposes of separation. Therefore, the separation of proteins based on their molecular weights is the main function of PAGE, making this the correct choice for the question provided.