Task: Please answer the multiple choice question.
Question: Which molecule has the highest rat LD50 (oral exposure)?
Constraint: Even if you are uncertain, you must pick either a or b without using any other words.
Options:
(a) O=C(NC(CCc1ccc2c(c1)OCO2)CCc1ccc2c(c1)OCO2)c1ccc(Cl)cc1
(b) C=CCn1c(=O)c2[nH]c(C)nc2n(CCCC)c1=O
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}