Due to increased demand for products, your privately held manufacturing company recently grew from $26$ full$-$time employees to more than $190.$ The organizational structure was flat, with most employees hired by you and reporting directly to you. Growth has forced you make the organization more hierarchical by$,$ promoting people from within to supervisory positions, but you are still the only person in an upper management position. Which of the following upper$-$level positions would be the BEST choice to add first in this situation?

$$ A$.$ A dynamic leader

B$.$ A structural engineer

C$.$ An advertising manager

D$.$ A diversity manager

E$.$ A human resource manager