$$\left( {4 + \sqrt 7 } \right),$$expressed as a perfect square, is equal to = ?

• A. ${\left( {2 + \sqrt 7 } \right)^2}$$
• B. ${\left( {\frac{{\sqrt 7 }}{2} + \frac{1}{2}} \right)^2}$$
• C. $\left\{ {\frac{1}{2}{{\left( {\sqrt 7+ 1} \right)}^2}} \right\}$$
• D. $\left( {\sqrt 3+ \sqrt 4 } \right)$$