Let R be an equivalence relation on Z given by aRb if 2 divides (a − b). The equivalence class [0] is:

Let R be an equivalence relation on Z given by aRb if 2 divides (a − b). The equivalence class [0] is:

• A. Set of all odd integers
• B. Set of all even integers
• C. {0, 2, 4}
• D. Z

Answer: B) Set of all even integers

Explanation: The equivalence class [0] contains all integers x such that xR0, which means 2 divides (x − 0) → 2 divides x. This defines the set of all even integers.