Given, $ {{({{x}^{2}}+{{y}^{2}})}^{2}}=4({{x}^{2}}-{{y}^{2}}) $ Graph of curve isClearly, it has two tangent is parallel of X-axis and two tangent is parallel to Y-axis Polor coordinate of curve is
$ {{r}^{2}}=4\,\cos \,2\theta $ Area of curve
$=\int_{-\pi /4}^{\pi /4}{{{r}^{2}}\,\,d\theta =4\,\,\int_{-\pi /4}^{\pi /4}{\cos \,2\theta \,\,d\theta }} $
$=8\int_{0}^{\pi /4}{\cos \,2\theta \,\,d\theta =8\left[ \frac{\sin \,2\theta }{2} \right]_{0}^{\pi /4}=4} $ Hence, area of curve is less than 4.
$ \therefore $ All of the options are true.