If $$5 \sin^2 \theta = 3(1 + \cos \theta), 0^\circ < \theta < 90^\circ$$, then the value of $$\cosec \theta + \cot \theta$$ is:

A

$$\frac{4}{\sqrt{21}}$$

B

$$\sqrt{\frac{3}{7}}$$

C

$$\frac{5}{\sqrt{21}}$$

D

$$\sqrt{\frac{7}{3}}$$