Final answer:
Norton's theorem permits the reduction of any two-terminal network of fixed resistances to one having a single voltage source and a parallel resistance.
Step-by-step explanation:
The statement is true. Norton's theorem states that any two-terminal network of fixed resistances can be reduced to a single voltage source and a parallel resistance. This equivalent circuit is obtained by replacing the original network with a current source in parallel with a resistance, where the current source is equal to the original current flowing through the terminals and the resistance is equal to the original network's resistance seen from the terminals.