\( \displaystyle \lim_{x\to 0} cosec x \left( \sqrt{2\cos^2 x + 3\cos x} - \sqrt{\cos^2 x + \sin x + 4} \right) \) is:
\( -\frac{1}{2\sqrt{5}} \)
\( 0 \)
\( \frac{1}{2\sqrt{5}} \)
\( \frac{1}{\sqrt{15}} \)