The isotopic composition of an unknown element is measured as follows.
m/z (amu) Relative abundance
64 48.6 %
66 28.0 %
67 4.1 %
68 19.3 %
Assuming all ions carry a +1 charge, which element is most consistent with the data?
a) Copper, 63.55 amu
b) Germanium, 72.63 amu
c) Zinc, 65.38 amu
d) Gallium, 69.72 amu