A 1.8 m tall boy is standing at some distance from a 12 m tall building. The angle of elevation from his eyes to the top of the building increases from 45° to 60° as he walks towards the building. Find the distance (in meters) he walked towards the building.

• A. \(\frac{{51\left( {\sqrt 3 + 1} \right)}}{{5\sqrt 3 }}\)
• B. \(\frac{{51\left( {\sqrt 3 - 1} \right)}}{{5\sqrt 3 }}\)
• C. \(\frac{{12\left( {\sqrt 3 - 1} \right)}}{{\sqrt 3 }}\)
• D. \(\frac{{12\left( {\sqrt {3 + 1} } \right)}}{{\sqrt 3 }}\)