Guess the missing item from this list: α-7, α-3, β-1, β-2, β-4, α-6, α-4, β-6, β-3, α-0, β-5, α-2, β-0, α-9, α-1, α-5.
Directly answer with only one item. Item format should match the list format. Provide no explanation. Answer format: "{item}."