Radioactivity: the Stability of Fe with Respect to Alpha

Radioactivity: The stability of Fe with respect to alpha, β⁺, and β^- decay is to be determined. Do not consider the possibility of decay by electron capture. The following atomic masses are known: He: 4.002603 u Cr: 51.944768 u Mn: 55.938907 u Fe: 55.934939 u Co: 55.939841 u The Fe nuclide is

A) not subject to alpha, β⁺, or β^- decay.
B) subject to alpha decay only.
C) subject to β⁺decay only.
D) subject to β^- decay only.
E) subject to β⁺ or β^- decay, but not to alpha decay.