What statement is true concerning a two-pipe hydronic heating system?

Correct Answer: Option B — Each heating coil inlet temperature is identical, as each parallel-connected heating coil has its own separate supply teeing off a supply main.

Two-pipe systems utilize parallel connections where each heating coil is supplied directly from the supply main and returns to a separate return main. This configuration ensures that every coil receives water at the same supply temperature, providing uniform heating performance across all zones regardless of their position in the circuit.