In the shown figure, if PS, UQ and RT are each perpendicular to PR, then _______

• A. \[\frac{1}{a}+\frac{1}{b}=\frac{1}{c}\]
• B. \[\frac{1}{b}+\frac{1}{c}=\frac{1}{a}\]
• C. \[\frac{1}{a}+\frac{1}{c}=\frac{1}{b}\]
• D. \[\frac{1}{c}+\frac{1}{a}=\frac{2}{b}\]
• E. None of these