When the primary direct crank of a reciprocating engine makes an angle of $$\theta $$ with the line of stroke, then the secondary direct crank will make an angle of _________ with the line of stroke.
A
$$\frac{\theta }{2}$$
B
$$\theta $$
C
$$2\theta $$
D
$$4\theta $$
Correct Answer: $$2\theta $$