Answer:
The true statement among the options is;
d. A real emf device has internal resistance and an ideal emf device does not.
Step-by-step explanation:
The internal resistance of an ideal emf device is zero to which allows the perfect movement of charges between terminals. This results in the emf of an ideal emf device being equal to the potential difference across the terminals of the device
By definition, an ideal emf device is an emf device with zero internal resistance
There is some level of resistance in a real emf device and the emf of the device is equal to the potential difference across its terminals only if there is no current flowing through it.