Consider the following spontaneous cell reactions: 
X + Z²⁺ → X²⁺ + Z
Y + Z²⁺ → Y²⁺ + Z
X + Y²⁺ → X²⁺ + Y
Identify the best oxidizing agent and the best reducing agent.

• A. Best oxidizing agent: X²⁺
  Best reducing agent: Y
• B. Best oxidizing agent: Y²⁺
  Best reducing agent: Z
• C. Best oxidizing agent: Z²⁺
  Best reducing agent: X
• D. Best oxidizing agent: X²⁺
  Best reducing agent: Z
• E. Best oxidizing agent: Y²⁺
  Best reducing agent: X
• F. Best oxidizing agent: Z²⁺
  Best reducing agent: Y

Answer: (C)