1 .

• A. $\left\{1,2,3,\frac{2}{3}, 5.....\right\}$
• B. $\left\{-\infty ,\infty \right\}$
• C. $\left\{Q U Q\text{'}\right\}$
• D. $\left\{\pm 1,\pm 2,\pm 3..... \right\}$

Answer: Option C

Explanation: