Which reduction half-reaction involves the species Am{4+)(aq)?
a. Am⁴⁺(aq) + e⁻ ⇌ Am³⁺(aq)
b. Tl³⁺(aq) + 2e⁻ ⇌ Tl⁺(aq)
c. Ac³⁺(aq) + 3e⁻ ⇌ Ac(s)
d. Cs⁺(aq) + e⁻ ⇌ Cs(s)