Determine whether the given word is a prefix, suffix, or root word.

auto

A.
prefix

B.
suffix

C.
root word

C. root word

C. root word

To determine whether the given word "auto" is a prefix, suffix, or root word, we need to understand the meanings and functions of these word parts.

1. Prefix: A prefix is a word part that is added at the beginning of the root word to change or modify its meaning. It usually does not stand alone as a word.

2. Suffix: A suffix is a word part that is added at the end of the root word to change its meaning or function. Like prefixes, suffixes typically do not function as standalone words.

3. Root Word: The root word is the main part of a word that carries the core meaning. It can stand alone as a word and does not require any additional parts to make sense.

Now, let's determine the nature of the word "auto":

- "Auto" is a recognizable English word itself, which means "self" or "automatic." It is derived from the Greek word "autos" meaning "self."

Based on this information, we can conclude that "auto" is a root word because it has its own meaning and does not contain any additional parts (prefixes or suffixes) that modify it.

Therefore, the correct answer is:

C. root word