Which of the Following Is Not Consistent with Observations of the Cosmic

Multiple Choice

Which of the following is not consistent with observations of the cosmic microwave background?

A) The universe is geometrically "flat" (in the four dimensions of spacetime) .
B) The matter density (both luminous and dark matter combined) in the universe is only about one-fourth of the critical density.
C) Dark energy, whatever it is, represents the majority of the energy content of the universe.
D) The universe is at least 20 billion years old.