Which type of interface is commonly used to connect a keyboard and mouse?

The correct answer is that a keyboard and mouse commonly use a PS/2 interface. The PS/2 port is a round connector that was traditionally used for connecting these input devices to a computer. This type of interface has been around since the 1980s and was the standard for many years.

While PS/2 ports are less common in modern systems, particularly as USB technology has become dominant, they remain significant for legacy systems and environments where retrofitting modern USB devices is not feasible. Additionally, PS/2 connections can provide advantages over USB in certain scenarios, such as supporting simultaneous key presses more effectively.

USB is another type of interface widely used today for keyboards and mice, often replacing PS/2 connections in modern hardware. However, the question specifically asks for a type of interface commonly associated with connecting these devices historically, which is best represented by the PS/2 interface.

HDMI is primarily used for video and audio connections, specifically for monitors and televisions, while VGA is an older analog video standard that does not connect keyboards or mice. Therefore, they are not relevant to this question regarding input devices.