The curve $a^{2}y^{2}=x^{2}(a^{2}-x^{2})$ has

Question

\[\](1)only one loop between$ x=0$ and $x=a$\[\](2)two loops between $x=0$ and $x=a$\[\](3)two loops between $x=-a$ and $x=a$\[\](4)no loop