Which logical fallacy is committed in the following argument? 'Atheists have not proven that God does not exist. Therefore, we can conclude that God exists.'

Consider the following argument: 'UGC NET toppers study 12–14 hours daily. Therefore, anyone who studies 12–14 hours daily will become a UGC NET topper.' The argument commits which of the following logical fallacies?

A fallacy in which a proposition is held to be true just because it has not been proved false, or false just because it has not been proved true, is called: