Number of terms in the expansion of ${[(x+\dfrac{1}{x})^{2}-(x-\dfrac{1}{x})^{2}]}^{1007}$ is ...

$\left [ \left (x+\dfrac {1}{x} \right)^2-\left (x+\dfrac {1}{x} \right)^2 \right]^{1007}$

$\Rightarrow \ \left [x^2+\dfrac {1}{x^2}+2-\left (x^2+\dfrac {1}{x^2}-2 \right) \right]^{1007}$

$\Rightarrow \ \left (x^2+\dfrac {1}{x^2}-x^2-\dfrac {1}{x^2} +2+2\right)^{1007}$

$x^2+\dfrac {1}{x^2}4^{1007}$

$x^2+\dfrac {1}{x^2}$ No. of term $:1$ Option $C$ is correct