Dunn and Brad Partnership Is Considered Insolvent and Has Liabilities

Dunn and Brad partnership is considered insolvent and has liabilities of $10,000.Here is a snapshot of the general ledger:
$$\begin{array} { | l | l | l | } \hline & \text { Dunn } & \text { Brad } \\\hline \text { Personal Assets } & \$ 40,000 & \$ 16,000 \\\hline \text { Personal Liabilities } & \$ 16,000 & \$ 20,000 \\\hline \text { Partners Capital } & \$ 20,000 & ( \$ 10,000 ) \\\hline\end{array}$$
What is Dunn's required contribution if the partnership creditors move against him first?

A) $16,000
B) $4,000
C) $10,000
D) $8,000