Answer:
It is the option B that is 'i'.
B. i
Explanation:
Given :
The square root of -1 written as
![√(-1)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/jm2id6uma960smgqa3ppe05cswxxlr65c7.png)
When there is a negative number in the square root it is called as an imaginary number.
And imaginary number is denoted by 'i'
and the value for i is
![√(-1)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/jm2id6uma960smgqa3ppe05cswxxlr65c7.png)
for an example
![√(-3) = √(3)* √(-1)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/l2jeze9oxs0woxb98aouipib58wnk3ktsk.png)
![= √(3)* i\\= √(3)i](https://img.qammunity.org/2020/formulas/mathematics/middle-school/7imh3ure43g6sl5ij1r97ihv40kxsois8a.png)
Hence the answer is 'i'.