Correct Answer - Option 4 : θ(n
m)
f(n) = a0 + a1n + a2n2 + a3n3 + .......amnm
a0 , a1, a2 ,a3 are constants & highest power of n is nm
So the complexity will be θ(nm)
Important Point
Big-Θ notation to asymptotically bound the growth of a running time to within constant factors above and below.