There is a theory that gravity could pull galaxies back together, causing a reverse big bang.

which observation makes this theory less likely than the idea that the universe may continue to expand?

background radiation is present.
galaxies exist outside of the milky way.
the expansion of the universe is accelerating.
gas giants form farther from the sun, where temperatures are cooler.

The expansion of the universe is accelerating.

Explanation: Every millisecond the expansion slowly but surely speeds up.

Sweet and juicy.

Explanation:

This is because sweet and juicy flavor happens to be a good and tasty flavor that everyone would love and it was developed to achieve these phenotypic trait by selectively breeding two different carrots species to achieve these desired traits. It was gotten after researches has been done to satisfy human desires of consuming something sweet and juicy.