A geostationary orbit is a circular orbit directly above the Earth's equator, 35,786 km above sea level. This specific altitude allows a satellite to revolve around the Earth at the same rotational speed as the Earth, making it appear stationary relative to a fixed point on the Earth's surface.

Let’s look into why 35,786 km is the correct answer:

1. Definition of Geostationary Orbit: A geostationary orbit is an equatorial, circular orbit with an altitude of approximately 35,786 kilometers. This orbit allows satellites to match the Earth's rotation, appearing stationary in the sky over a specific point.
2. Calculation Verification: The altitude ensures that the satellite has a period of 24 hours, matching the Earth's rotational period. The gravitational force acting as the centripetal force ensures it maintains this orbit:
3. Simplified Formula: The orbital altitude (h) can be calculated by solving the gravitational force balance equation, given by: \(R_{\text{Earth}} + h = \left(\frac{GM_{\text{Earth}}}{4\pi^2}\cdot T^2\right)^{1/3}\), where \(T\) is 24 hours, \(G\) is the gravitational constant, \(M_{\text{Earth}}\) is the mass of the Earth, and \(R_{\text{Earth}}\) is the Earth's radius (approximately 6,371 km).
4. Exact calculation confirms that \(h\) is approximately 35,786 km above the Earth's surface.
5. Conclusion: The correct and standard distance for a geostationary orbit is therefore 35,786 kilometers, making the answer 35,786 km.

Hence, the height of the geostationary orbit is 35,786 km.