Based Solely on the Fact That, for Elements Beyond Bi-209

Multiple Choice

Based solely on the fact that, for elements beyond Bi-209 all nuclei are unstable and radioactive, we can conclusively determine that

A) in order to be radioactive, an element must have a mass of at least 210
B) polonium-210 is radioactive, but polonium-208 and polonium-209 are not radioactive
C) both uranium-235 and uranium-238 are radioactive
D) phosporus-32 and sulfur-35 are not radioactive
E) lead does not have radioactive isotopes