Answer:
Option B is correct.
Step-by-step explanation:
We have been given a point on unit circle defined by real number theta.
So, tan theta is the given by:[tex]tan\theta=\frac{y}{x}[/tex]
Equation of unit circle is [tex]x^2+y^2=1[/tex]
Where 1 is the radius.
Therefore, Option B is correct that is [tex]tan\theta=\frac{y}{x}[/tex]