Question

what is the main function of the floor area ratio (far) in architectural planning?
far dictates the number of plumbing fixtures per floor.
it controls roof pitch and angle to preserve views.
far is only used for agricultural land conversions.
it regulates total building bulk in proportion to lot size.

Explanation:

The floor - area ratio (FAR) is a key zoning regulation. It is the ratio of a building's total floor area to the size of the lot it is built on, and thus regulates building bulk relative to lot size. The other options are incorrect as FAR has nothing to do with plumbing fixtures per floor, roof pitch/angle, or is not only for agricultural land conversions.

Answer:

It regulates total building bulk in proportion to lot size.