The __________ rule makes it possible to define different style rules for different media types in the same stylesheet.

The correct answer is: C. @media

The @media rule is a CSS at-rule that allows you to specify different styles for different media types. For example, you could use the @media rule to specify different styles for print and screen media.

The @media rule takes a media type as its argument. The media type can be any of the following:

• all
• audio
• braille
• embossed
• handheld
• print
• projection
• screen
• speech
• tty
• tv

The @media rule can also take a list of media types as its argument. For example, the following rule would specify different styles for print and screen media:

“`css
@media all and (min-width: 600px) {
/ Styles for screen media /
}

@media print {
/ Styles for print media /
}
“`

The @media rule can be used to specify different styles for different devices. For example, the following rule would specify different styles for mobile devices and desktop computers:

“`css
@media all and (max-width: 600px) {
/ Styles for mobile devices /
}

@media all and (min-width: 600px) {
/ Styles for desktop computers /
}
“`

The @media rule can also be used to specify different styles for different output devices. For example, the following rule would specify different styles for a printer and a screen:

“`css
@media print {
/ Styles for a printer /
}

@media screen {
/ Styles for a screen /
}
“`

The @media rule is a powerful tool that can be used to create responsive web designs. By using the @media rule, you can specify different styles for different devices and output devices. This allows you to create a web design that looks great on all devices.

The other options are incorrect because they are not valid CSS at-rules.