The Mass of a Proton Is 1

The mass of a proton is 1.00728 amu and that of a neutron is 1.00867 amu. What is the mass defect (in amu) of a nucleus? (The mass of a cobalt- 60 nucleus is 59.9338 amu.) .?

A) 0.0662
B) 0.5405
C) 27.7830
D) 0.4827
E) 0.5489