Describe which organizational structure would a small physician's office use and why?

The purpose of an organizational structure chart for use in a small physician's office is to show the ideal structure of the physician's practice.  This chart includes the functional relationships between the various components of the chart. The reason for this chart is to help the  practice improve its business processes which in turn will increase the efficiency of the staff who work in the practice. This in turn, will improve the ability of the physician to consult with more people. The end result being that more people will be helped.

Answerfarmer's market; (b) would be my second choice

The attention line is placed above the recipient line, that is, above the name of the firm to which the mail-piece  is directed.