Answer:
A. General Adaptation Syndrome
Explanation:
General Adaptation Syndrome as described by Hans Selye, is a phenomenon or reactional but physiological, process which is in three stages; alarm, resistance and exhaustion, that a body will experience when under stress.
Hence, in this case, Greg's response to stress is General Adaptation Syndrome,because as his muscle tightens and developed a stiff neck, that's ALARM stage.
However, by taking more frequent breaks, leaning back in the desk chair, and staring off into space, Greg's response to stress is in stage two, which is RESISTANCE stage; as the body shifts from alertness to repairs.
And lastly, byshowing signs of sore throat and headache, this is EXHAUSTION stage, as the body, has no more energy to cope with the stress, hence, the deterioration continues.