When Californium-249 is bombarded by Oxygen-18, a new isotope and four neutrons are produced. Express your answer as a nuclear equation.
a) Cf-249 + O-18 → Cf-250 + 4n
b) Cf-249 + O-18 → Cf-250 + 2n
c) Cf-249 + O-18 → Cf-251 + 4n
d) Cf-249 + O-18 → Cf-251 + 2n