The correct answer is: Designers generally use one font style and one font size in an interface.
A font style is the appearance of a font, such as its weight, italicization, or boldness. A font size is the size of the characters in a font.
Designers generally use one font style and one font size in an interface to create a consistent and easy-to-read design. Using multiple font styles and sizes can make an interface look cluttered and difficult to use.
There are a few exceptions to this rule. For example, designers may use different font styles to indicate different types of content, such as headings and body text. They may also use different font sizes to emphasize important information. However, these exceptions should be used sparingly, as they can make an interface look less consistent.
In general, it is best to use one font style and one font size in an interface to create a clean and easy-to-read design.