Give the formula for the n-th roots of z = r(cos θ + i sin θ) (n ∈ ℕ).

A r^(1/n)[cos(θ/n) + i sin(θ/n)] only

B r^(1/n)[cos((θ + πk)/n) + i sin((θ + πk)/n)], k = 0,…,n−1

C r[cos(θ + 2πk) + i sin(θ + 2πk)], k = 0,…,n−1

D r^(1/n)[cos((θ + 2πk)/n) + i sin((θ + 2πk)/n)], k = 0,…,n−1

Correct Answer: Option D