Final answer:
The discovery of Saturn's largest moon Titan was made by Christiaan Huygens, not Jan Hendrik Oort, and the Huygens probe, named after the astronomer, was indeed the first and only probe to land on Titan's surface.
Step-by-step explanation:
The statement that Jan Hendrik Oort discovered Saturn’s largest moon Titan is false. Titan was discovered by the Dutch astronomer Christiaan Huygens in 1655.
The first and only probe to land on Titan's surface is indeed named after Christiaan Huygens, and it is called the Huygens probe. This probe was part of the Cassini-Huygens mission, a cooperative venture between NASA and the European Space Agency.
Huygens made its historic landing on Titan on January 14, 2005, providing valuable data including imagery of the landing site for about 90 minutes. This makes the landing of the Huygens probe the first and so far only spacecraft landing on a moon in the outer solar system.