$A I N$ pendulum bob is held at an angle $\theta$ from the vertical by a $2\;N$ horizontal force $\overrightarrow {F}$ as shown in figure. The tension in the string supporting the pendulum bob (in Newtons) is

Question

 

\[\begin {array} {1 1} (a)\;\cos \theta & \quad (b)\;\frac{2}{\cos \theta} \\ (c)\;\sqrt 5 & \quad (d)\;1 \end {array}\]