Hahn Banach extension type theorem

Question

Let $V$ be a Banach space and $M_{n}$ be a $n\times n$ matrix over $\mathbb{C}$. Let $T: V\mapsto M_{n}$ be a bounded linear operator. Then there is a norm preserving linear extension $\widetilde{T}$ of T from $V^{**} \mapsto M_{n}$. We note that norm of $M_{n}$ is taken from this isomorphism $M_{n}\cong B(\mathbb{C}^{n},\mathbb{C}^{n})$.
If anybody give idea to solve it will be appreciated