【单选题】
函数<img class="kfformula" src="20190808/1565253438624934.png" data-latex="y=2-{x}^{2}"/>的单调递减区间是（ ）
①
<img class="kfformula" src="20190808/1565253438467999.png" data-latex="\left ( {-\infty ，0} \right )"/>
②
<img class="kfformula" src="20190808/1565253438403956.png" data-latex="\left ( {-\infty ，-1} \right )"/>
③
<img class="kfformula" src="20190808/1565253438303182.png" data-latex="\left ( {-1，+\infty } \right )"/>
④
<img class="kfformula" src="20190808/1565253438117832.png" data-latex="\left ( {0，+\infty } \right )"/>