Plssss help fasttt , I’ll mark u as the brainlest and follow u too

[tex]\huge\color{lime}\boxed{\colorbox{black}{Answer : - }}[/tex]
sec² θ (1 + sin θ) (1 - sinθ ) = k
sec² θ(1-sin²θ ) = k
sec² θ cos² θ = k
sec² θ. 1 /sec²θ = k
1 = k
.. k = 1.