Which of the following options is/are correct for the Automatic Generation Control (AGC) and Automatic Voltage Regulator (AVR) installed with synchronous generators?
- AGC response has a local effect on frequency while AVR response has a global effect on voltage.
- AGC response has a global effect on frequency while AVR response has a local effect on voltage.
- AGC regulates the field current of the synchronous generator while AVR regulates the generator's mechanical power input.
- AGC regulates the generator's mechanical power input while AVR regulates the field current of the synchronous generator.