Key Concept: Solar panels and batteries generate DC, but the electrical grid and most appliances run on AC.
Why it's correct: An inverter's defining job is converting DC (from panels/batteries) into AC, making that power usable by standard household and industrial equipment.
Why others fail: Storing energy is a battery's role, boosting voltage is a transformer's role, and regulating current is a separate controller function — none of these is what 'inverting' means.