Task: Please answer the multiple choice question.
Question: Which molecule has the highest acute oral toxicity rat LD50?
Constraint: Even if you are uncertain, you must pick either a, b, c, or d without using any other words.
Options:
a. CC(=O)NC(=O)c1ccccc1O
b. CCOP(=S)(CC)Sc1ccccc1
c. O=[N+]([O-])c1ccccc1O
d. COP(=S)(OC)Oc1ccc([N+](=O)[O-])c(C)c1
Answer: a
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}