[单选题]
The Q value for a particular reg.i 9sm8wq6o saction is -2.4 MeV, and the reacti ;inyog dp3,;:hlc e:xon's threshold energy is 9.60 MeV. What is the ratio of the mass of the incident particle to the mass of the stationary t:ge ;xhcdo yil:3;np, arget nucleus?