Answer:
an independent clause
Step-by-step explanation:
An independent clause can be defined as a clause that expresses a complete thought while standing alone as a simple sentence and comprises of at least a subject and a verb (predicate)
Hence, the characteristics of an independent clause are;
I. It contains a subject and a verb.
II. It is used to express a complete thought.
III. It can stand alone as a complete sentence.
Therefore, the string of words: "When we look at severe concussions" is an independent clause.