Affect(s) the amount of air conditioning required.

the number of occupants

the activity of the occupants

the number of appliances operating in the room

all of the above

Option D

All the above

Explanation:

Depending with the number of occupants in a building, the number of air conditioners required can either be increased or reduced. For instance, if the building is to be a classroom of over 50 students, 1 air-conditioner can't serve effectively. Similarly, the activity of occupants also dictate the amount of air conditioners required since if it's a gym room where occupants exercise often then the air conditioners required is different from if the room was to serve as a  lounge. The appliances that also operate in a room require that air conditioners be installed as per the heat that may be generated by the appliances.