Which one of the following techniques can be used to determine the mass of a planet most easily?

Question

Quizplus · Accepted Answer

Measuring the period and size of the orbit of a satellite moving around a planet can provide information about the planet's mass through the application of Kepler's laws of motion. This technique is commonly used in the study of our solar system and has been used to determine the masses of planets such as Jupiter and Saturn. Direct observation of size (A) or observing the spectrum of radiation reflected from its surface (D) do not provide sufficient information to determine mass, while observing the "wobble" of the Sun (B) is a technique used to detect exoplanets but requires more complex calculations to determine the planet's mass.

Which One of the Following Techniques Can Be Used to Determine