かく分裂 ぶんれつ反応 はんのうでしょう
kakubunretsuhannōdeshō

Noun
Desu Copula

Expresses probability in a polite manner ("probably…") of 核分裂反応

1. Probably a nuclear fission reaction.; It will likely be a nuclear fission reaction.

Polite
Presumptive
Conjecture