Which one of the following planets was explored by Cassini Mission launched by NASA, which ended in September 2017?

The Cassini-Huygens mission was a collaborative space exploration project involving NASA, the European Space Agency (ESA), and the Italian Space Agency (ASI) specifically designed to explore Saturn [1]. Launched in October 1997, the spacecraft spent nearly 20 years in space, including 13 years orbiting the ringed planet. During its mission, it conducted extensive studies of Saturn's atmosphere, rings, and moons, notably deploying the Huygens probe onto the surface of Titan. The mission concluded with a 'Grand Finale' on September 15, 2017, when the spacecraft was deliberately plunged into Saturn's atmosphere to prevent biological contamination of its potentially habitable moons, such as Enceladus and Titan. While the probe performed a flyby of Jupiter in 2000 to gain a gravity assist, its primary scientific destination and the site of its 2017 end was Saturn [1].

Sources

1. [1] https://www.jpl.nasa.gov/missions/cassini-huygens/