A graph shows the horizontal line $y=4$. Which statement correctly describes its domain and range?

• A. Domain: $x=4$ Range: $y\in (-\infty ,\infty )$
• B. Domain: $x\in (-\infty ,\infty )$ Range: $y\in (-\infty ,\infty )$
• C. Domain: $x\in (-\infty ,\infty )$ Range: $y=4$
• D. Domain: $x\in (-\infty ,4)$ Range: $y\in (4,\infty )$

Answer: (C)