Under What Circumstances Does a DIRECT Interlocking Directorate Exist

Under what circumstances does a DIRECT interlocking directorate exist?

A) when both management and the board establish corporate strategic management
B) when a corporation's employees are included on its board
C) occurs when two firms share a director or when an executive of one firm sits on the board of a second firm
D) when all board members are also employed by the corporation
E) when two corporations have directors who serve on the board of a third firm