From a lighthouse the angles of depression of two ships on opposite sides of the light house are observed to be 30° and 45°. If the height of the lighthouse is h metres, the distance between the ships is

• A. $\left( {\sqrt 3+ 1} \right)\,h\,{\text{metres}}$$
• B. $\left( {\sqrt 3- 1} \right)\,h\,{\text{metres}}$$
• C. $\sqrt 3 \,h\,{\text{metres}}$$
• D. ${\text{1 + }}\left( {1 + \frac{1}{{\sqrt 3 }}} \right)\,h\,{\text{metres}}$$