Physical variables suggests that the actual layout of the work environment, temperature, noise-level are important factors in work related stress.
Option: B
Step-by-step explanation:
In any workplace, a person's performance depends upon several factors. Physical variables, mental challenges, contacts with other persons, accountability, managing capacity etc. When a person wants to give his best in his work place the above mentioned conditions should be in favour of him.
Weather (mainly temperature), noise level (loud horns, sound system, shouting), behaviour of other colleague towards him which creates some time anxiety or mental pressure, huge work load, interaction with other staff members etc. These plays a vital role in controlling the work related stress or the overall work environment.