Task: Please answer the multiple choice question.
Question: Which molecule has the highest acute oral toxicity (LD50 in rats)?
Constraint: Even if you are uncertain, you must pick either a, b, c, or d without using any additional words.
Options:
a: O=C(O)C1CCc2cc(C3CCCCC3)ccc21
b: O=c1oc2ccccc2c(O)c1C1CC(c2ccc(-c3ccc(Br)cc3)cc2)Cc2ccccc21
c: NC(=O)Cc1c([O-])on[n+]1Cc1ccccc1
d: C(=Nc1ccccc1)Nc1ccccc1
Answer: d
Task: Please answer the multiple choice question.
Question: Which molecule has the highest {acute_toxicity__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%acute_toxicity%}
Answer: {%multiple_choice_result}