Solution:

(i) C = { is a two-digit natural number such that the sum of its digits is 8}

17, 26, 35, 44, 53, 62, 71, and 80 are the only elements of the given set

As a result, the provided set can be written in the roster form as

C = {17, 26, 35, 44, 53, 62, 71, 80}

(ii) D = { is a prime number which is divisor of 60}

Now here 60 = 2 × 2 × 3 × 5

2, 3 and 5 are the only elements of the given set

As a result, the provided set can be written in the roster form as

D = {2, 3, 5}