What is the simplified value of $$\frac{\sin^3 21^\circ + \cos^3 19^\circ}{\sin 21^\circ + \cos 19^\circ} + \sin^2 69^\circ + \cos^2 71^\circ + \frac{1}{\sec 69^\circ \cosec 71^\circ}$$ is:

A

2

B

1

C

4

D

3