Final answer:
The file extension commonly used for most GIMP script plugins is .scm.
The answer is option ⇒D. .scm
Step-by-step explanation:
This stands for Script-Fu files which is a language built within GIMP for the creation of scripts and plugins. While JPEG, which stands for Joint Photographic Experts Group, is a format used for digital photos and uses the extensions . jpeg or . jpg, it is not the right answer in the context of GIMP script plugins.
The two main reasons the JPEG format is used for digital photos are because it can display millions of colors and it is compressed to create smaller image files while still maintaining a good quality image.
The answer is option ⇒D. .scm