Non-verbal communication is the correct answer.
Non-verbal communication is a type of communication that does NOT involve words. This type of communication is done through gestures, facial expressions, the tone of voice, the posture and distance between two people who are communicating.
A clinical trail
Clinical trials are research studies that explore whether a medical strategy, treatment, or device is safe and effective for humans. These studies also may show which medical approaches work best for certain illnesses or groups of people. - Definition by <span>https://www.nhlbi.nih.gov/studies/clinicaltrials</span>
Answer:
Ecosystem stability is an important corollary of sustainability. Over time, the structure and function of a healthy ecosystem should remain relatively stable, even in the face of disturbance. If a stress or disturbance does alter the ecosystem is should be able to bounce back quickly.
Explanation: