Task: Please answer the multiple choice question.
Question: Which molecule has the longest half life time in humans after IV administration?
Constraint: Even if you are not sure, you must pick either a, b, c, or d without using any other words.
Options:
a: O=NN(CCCl)C(=O)NCCCl
b: CCCC(C)C1(CC)C(=O)NC(=O)NC1=O
c: NCC[C@H](O)C(=O)N[C@@H]1C[C@H](N)[C@@H](O[C@H]2O[C@H](CN)[C@@H](O)[C@H](O)[C@H]2O)[C@H](O)[C@H]1O[C@H]1O[C@H](CO)[C@@H](O)[C@H](N)[C@H]1O
d: C[C@H](Cn1cnc2c(N)ncnc21)OCP(=O)(O)O
Answer: a
Task: Please answer the multiple choice question.
Question: Which molecule has the longest {half_life_duration__names__noun}?
Constraint: Even if you are {#uncertain|not sure!}, you must pick either {%multiple_choice_enum%2-5%aA1} without using any {#other|additional!} words.
Options:
{SMILES%half_life_duration%}
Answer: {%multiple_choice_result}
1,3-bis(2-chloroethyl)-1-nitrosourea