Which of the Following Is NOT a Criterion for Use

Which of the following is NOT a criterion for use of a compound in intravenous diagnosis or therapy?

A) The compound must be soluble in blood if injected intravenously.
B) The compound must be infinitely stable.
C) The compound must be stable enough to avoid elimination from the body.
D) Radionuclides used in medicine must have short half-lives.
E) Nuclide selection is governed by the toxicity of the parent compound.