Supported. We're told that the second theory, which questions the gravitational predictions of the theory of relativity, can be tested in our own solar system.

Anti-supported. Astronomers believed the universe was expanding, but thought that the rate of expansion was decreasing rather than increasing.

Not supported. We don't know why particle physicists originally postulated virtual particles. Dark energy theorists believe the virtual particles are relevant to dark energy, but this doesn't imply that the particle physicists had dark energy theory in mind when they first came up with virtual particles.

Not supported. The idea that Einstein's theory of relativity makes wrong predictions about gravity across very large distances is the second theory described in the last paragraph. But the author never indicates that the best available evidence supports this theory. Rather, the author notes that this theory is easier to test than the dark energy theory. But this doesn't tell us what existing evidence supports.

We're told Einstein proposed the cosmological constant to explain why the universe isn't shrinking under its own gravity. This constant was designed to describe some type of pressure that keeps the universe from shrinking. But we don't know that Einstein was even aware of the theory of vacuum energy or that virtual particles might create vacuum energy. So it wouldn't make sense to say that Einstein proposed the cosmological constant to describe the pressure from virtual particles.