Answer:
Let f be a function. If any horizontal line intersects the graph of f more than once, then f does not have an inverse. An absolute value function (without domain restriction) has an inverse that is NOT a function. That's why an absolute value function does not have an inverse function。
According to the data i feel that the sign between the two sets is union therefore -1&5DONT COMEin first set therefore according to me ans is c