The correct answer is C. Paper clip icon.
A GIF icon is an image file format that is used to create animated images. A stationery icon is a graphic that is used to customize the appearance of an email. An emoji icon is a small image that is used to express emotions or ideas. A paper clip icon is an image that is used to represent an attachment in an email.
When you are composing an email, you can attach files to it by clicking on the paper clip icon. This will open a window where you can select the files that you want to attach. Once you have selected the files, they will be added to your email.
The paper clip icon is a common symbol for attachments, and it is used in most email programs. It is a simple and easy-to-understand icon that makes it clear that you can add files to your email.