C is your answer it let communist countries under the USSR to transition over to Capitalism
There are in all 23 vital mementoes left behind by the 12 expeditors who visited the Moon as a part of the Apollo project. These include the 3 Lunar Roving Vehicles used to taxi around the surface of the Moon that were used during the mission Apollo-15, 16 and 17. Not only these expensive vehicles were abandoned there but all the 6 lunar modules which were used for the purpose of landing on the Moon are also left there. The other things, scattered across on the Moon, include the bags used to carry the life support systems, Neil Armstrong's as well as other astronauts' shoes, a device to measure the earthquake-like tremors on the Moon, a laser reflector which is used to measure the distance between the Earth and the Moon, the golf stick along and a golf ball that was struck by Alan Shepard, the national flag of the USA, the urine collection bags of the astronauts, tools used to break the rocks, etc. Personal belongings like the astronauts' family photographs are also included in the list. Every spot of human landing on the Moon includes some or the other thing to mark his visit on that spot.
Other mementos also include the first footprint of Neil Armstrong, the first man to land on the Moon as well.
Nixon when to China in 1970s to normalize relations and met with Zhou Enlai
A group of bishops or one pope
