-2 Which of the following are equal to n? of ni = (1 + i)an (ii) 1 + an-11 ni Snju ni = 1 + v + v2 + ... + vn (iv) Select one: a. (i) and (ii) only b. () and (iv) only c. (i), (ii), and (iv) only d. (i), (i), and (iii) only