Kepler's of planetary motion station states that the planets have an elliptical orbit, with the sun at one focal point the ellipse.
a. 3rd law
b. 1st law
c. 2nd law

B) 1st Law

Explanation:

Kepler's planetary motion is as following

1) Law of orbit : all planets revolve around sun in elliptical orbit with Sun as one of its focii

2) Law of Area : All planets revolve around sun with equal area cover in equal interval of time with respect to the position of the Sun

3) Law of time period : Square of the time period of motion of planet is proportional to the cube of semi-major axis of the planet around the sun.

So here the law which defines the orbit of the planets and its shape is the first law

so correct answer will be

B) 1st Law