Final answer:
An anatomical term consisting of more than one word root joined together with an 'o' is known as a combining form.
Step-by-step explanation:
An anatomical term consisting of more than one word root joined together with an 'o' is known as a combining form.
Combining forms are used in medical terminology to create words that describe specific structures or conditions in the body. For example, the combining form 'cardio-' means 'heart,' and when combined with '-logy' (meaning 'study of'), it forms the word 'cardiology' meaning the study of the heart.
So, the correct answer to the question is 1) Combining form.