Answer:
The expression "i 20 1" is not well-defined and requires more context to determine its meaning. It is possible that "i" refers to the imaginary unit, while "20" and "1" could be operands or arguments for a mathematical operation or function. Without knowing the specific operation or function, it is impossible to determine the value of the expression. The list of options provided (1, -1, -i, i) are also not applicable without further information.