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, b, c, d, or e without using any other words.
Options:
a. O=c1[nH]cc2ncnc-2[nH]1
b. NC1CCCCC1
c. Cc1oc(C)c(C(=O)Nc2ccccc2)c1C
d. CCCCN(CCN(CCCC)C(=O)N1CCOCC1)C(=O)N1CCOCC1
e. CCOP(=S)(Oc1ccc([N+](=O)[O-])cc1)Oc1ccc([N+](=O)[O-])cc1
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}