Which hypothetical universe will eventually contract, if there were no dark energy?

Question

Quizplus · Accepted Answer

The universe with 1.5 times the critical density of matter. This is because a universe with less than the critical density of matter (0.5 times in choice A) would expand forever, whereas a universe with more than the critical density of matter (1.0 times in choice C) would eventually stop expanding but not contract. The universe with 1.5 times the critical density of matter would have enough matter to eventually stop expanding and start contracting, but not enough to overcome gravitational attraction and prevent eventual collapse. Without dark energy to balance out gravitational attraction, this universe would eventually contract.

Which Hypothetical Universe Will Eventually Contract, If There Were No