Which Observation Regarding the Likelihood of Life Existing Elsewhere in the Universe

Multiple Choice

Which observation regarding the likelihood of life existing elsewhere in the universe has NOT yet been made?

A) the discovery of assemblies of organic molecules into cell-like, self-replicating structures in the soils of Mars and the atmosphere of Venus
B) the discovery of long-chain carbon-based molecules in interstellar clouds by radio astronomers
C) the manufacture of organic compounds in laboratory simulations of primordial planetary atmospheres
D) the discovery of long-chain amino acid protein molecules in meteorites