Choose the correct statement. A chain reaction occurs when a neutron stikes a nucleus and another proton is emitted. A chain reaction occurs when a neutron stikes a nucleus and is just absorbed. A chain reaction occurs when a neutron stikes a nucleus and another neutron is emitted.

chain reaction occurs when a neutron strikes a nucleus and another neutron (or more than one) is emitted. The emitted neutron can then go on to strike another nucleus, causing the release of further neutrons, and so on. This exponential increase in the number of reactions is what characterizes a chain reaction.<br />