UPSC NDA Math Model Paper 1

Given: f(x)=sin2(x)+3‌cos‌x−5
Let's calculate f(−x)
⇒f(−x)=sin2(−x)+3‌cos(−x)−5
⇒f(−x)=(−1)2sin2(x)+3‌cos(x)−5 --------------(∵ sin x is an odd function and cos x is an even function)
⇒f(−x)=f(x)
So, f(x) is an even function.
Hence, option A is the correct answer.