According to Wikipedia, "it is deemed unlikely that ZFC harbors an unsuspected contradiction; it is widely believed that if ZFC were inconsistent, that fact would have been uncovered by now". (https://en.wikipedia.org/wiki/Zermelo%E2%80%93Fraenkel_set_theory#Consistency).

This will resolve to YES if a proof of a contradiction is published in a peer-reviewed scientific journal on mathematical logic or a similar area, such as the Journal of Mathematical Logic, or if a majority vote of at least 5 researchers in mathematical logic agree that such a result published elsewhere is correct, before the start of 2050. Otherwise, this will resolve to NO at the start of 2050.