[单选题]
The process during which a heavy nucleus such as uranzr :o t- 6fe*oul-gz ul.qei+0ium splits into two i+ii or-d91 qtcy7xi9 8qp9otza xl +3antermedi1 qoazxty x7i+t 99pid8 3+qal-ci or9ate-sized nuclei after being struck by a neutron is referred to as
