What Is the Specific Activity (In Ci/g) of an Isotope

Multiple Choice

What is the specific activity (in Ci/g) of an isotope if 3.56 mg emits 4.26 × 10⁸ β particles per second?

A) 0.003232 Ci/g
B) 0.0115 Ci/g
C) 0.309 Ci/g
D) 3.23 Ci/g
E) None of these choices are correct.