Which of these describes Kepler’s third law of orbital motion?(1 point)

Kepler's third law of orbital motion states that the square of the orbital period \( T \) of a planet is directly proportional to the cube of the semi-major axis \( a \) of its orbit. This is commonly expressed as:

\[ T^2 \propto a^3 \]

So the correct response from your options is:

**T² ∝ a³**