Answer:
C. looking for word parts you may already know.
Step-by-step explanation:
This is one of the most effective ways of decoding the meaning of a technical word such as cardiorespiratory. While all the other options require more material or knowledge, this strategy relies on the knowledge you might already possess. It is a good idea to look for word parts that you may already know. In this case, you might know that "cardio" is associated to the heart and "respiratory" to breathing.