Supervisor A has trouble getting along with Supervisor B$,$ whose unit furnishes material for A$\text{'}$s unit. Of the following actions A might take, the best would be to:

Select the single best answer:

A$.$ avoid contact with $B$ as much as possible.

$B.$ tell his superior officer that he wishes $B$ were more cooperative.

C$.$ communicate with $B$ through a third party, to avoid worsening relations.

D$.$ seek to multiply his contacts with $B,$ with a view to establishing closer understanding.