Final answer:
The absolute value equation 0 = |-j| has one solution, which occurs when the variable j is equal to 0.
Step-by-step explanation:
The equation in question is 0 = |-j|. This is an absolute value equation, where |-j| represents the absolute value of -j. The absolute value of a number is always non-negative, meaning it is either positive or zero. Since the absolute value is set equal to zero, there is only one possible solution for j that satisfies this condition: when j is 0 itself. Therefore, the answer to how many solutions the equation has is b. one solution.