Some isolated 235U atoms will spontaneously fission into ... ...

   Some isolated 235U atoms will spontaneously fission into two approximately equal-sized fragments. The following represents a possible reaction: image What is missing from the right side of the reaction?
(A) A proton.
(B) ...
(C) ...
(D) ...
(E) ...

*This question is included in 16. Atomic and Nuclear Physics