If i2k= 1, and i2= -1. Which of the following must be true about k ?

Explanation

in = 1 if and only if n is a multiple of 4. (i4 = 1, i8= 1, i12 = 1, etc.) Therefore, if i2k = 1, then 2k must be a multiple of 4, and therefore, k must be a multiple of 2. When the power is even the answer is 1 or else it is -1. Option B: K is not a positive integer as the answer would then be negative Option C: k is a multiple of 2 and multiplying k with 2, the answer produced would be an even number which would not be completely divisible by 4 and would not give 1 as the remainder, for e.g 2(4)/4=2 Option D: k is supposed to be a multiple of 2 e.g 10/4 = 2.5 , the answer is not going to be an even integer.