Which statement is true? the perfect cosmological principle is the basis for the oscillating universe theory. the oscillating universe theory suggests that the universe will expand forever. the perfect cosmological principle is the basis for the big bang theory. the perfect cosmological principle is the basis for the steady state theory.

The cosmological principle has first been clearly stated by Isaac Newton in the "Philosophiae Naturalis Principia Mathematica" in 1687. He proved with mathematical  proofs on detailed observational data the principle of “universal gravitation”. The oscillating theory is a cosmological model which suggests that the universe we live in is a one of an innumerable series.  

Question: Which statement is true?

B. The oscillating universe theory suggests that the universe will expand forever.

The perfect cosmological principle states that the universe will always have the same characteristics and will always look the same. This theory have been "fixed" regarding the theory that the universe is still expanding, saying that while expanding, other masses will fill the expanding space although, the idea got dropped. We can conclude that the true statements is: "The perfect cosmological principle is the basis for the steady state theory.