The Circle or Ellipse Shown in the Calculator-Generated Graph Was $y_{1}$

Multiple Choice

The circle or ellipse shown in the calculator-generated graph was created using function mode with a square viewing window. What are the two functions $y_{1}$ and $y_{2}$ that were used to obtain the graph whose equation is given?
- $\frac{x^{2}}{25}+\frac{y^{2}}{25}=1$

A) $y_{1}=\sqrt{25-x^{2}}, y_2=-\sqrt{25-x^{2}}$

B) $y_{1}=\sqrt{25+x^{2}}, y_{2}=-\sqrt{25+x^{2}}$

C) $y_{1}=\sqrt{5+x^{2}}, y_{2}=-\sqrt{5+x^{2}}$

D) $y_{1}=\sqrt{5-x^{2}}, y_{2}=-\sqrt{5-x^{2}}$