Endings are added to roots.
Roots, or also referred to as base words, are the most basic parts of a word which provide the basic meaning of a word. The root is a word that does not have a prefix in front of the word or a suffix at the end of the word. A root must have an affix, or another root, attached to it in order to make it a whole word.
Answer:
d. "earthquakes occur when the edges suddenly become unstuck and slip along a fault"
Explanation: this one gives you the most detailed and informational sentence
