Choose the word which is different from the rest.

The answer is D. Saucer.

A beaker is a laboratory glassware piece with a flat bottom and vertical sides. It is used to measure and mix liquids. A glass is a drinking vessel made from glass. It is typically cylindrical in shape with a flat bottom and a rim. A mug is a large cup with a handle. It is typically used for hot drinks such as coffee or tea. A cup is a small drinking vessel with a handle. It is typically used for cold drinks such as water or juice. A saucer is a small plate that is placed under a cup or bowl. It is typically used to prevent spills and to protect the surface of the table.

The saucer is the only item in the list that is not used for drinking.