Lamp and light emitting diode tube thereof

A lamp, comprising:

• a tube holder comprising a first terminal socket and a second terminal socket, wherein the first terminal socket is electrically connected to a power source;
• and
• a light emitting diode tube installed on the tube holder, wherein one end of the light emitting diode tube comprises two first conductive terminals plugging in the first terminal socket, the light emitting diode tube comprises:
• a light emitting diode module with at least one light emitting diode string,
• two second conductive terminals disposed on the other end of the light emitting diode module and plugging into the second terminal socket, wherein the two second conductive terminals are shorted;
• a first conductive line;
• a second conductive line, wherein one end of the first conductive line and one end of the second conductive line are electrically connected to the plug, the other end of the first conductive line is electrically connected to one of the first conductive terminals, and the other end of the second conductive line is electrically connected to one of the second conductive terminals;
• a third conductive line;
• a fourth conductive line;
• and
• a short-circuit device, wherein one end of the third conductive line is electrically connected to the other one of the first conductive terminals, one end of the fourth conductive line is electrically connected to the other one of the second conductive terminals, and the short-circuit device is connected with the other end of the third conductive line and the other end of the fourth conductive line so as to short the third conductive line and the fourth conductive line.