Final answer:
b) boiler BTU input / 676,000. A boiler horsepower (BHP) is a unit of measurement used to describe the power output of a boiler. It is equivalent to 33,475 BTU per hour.
Step-by-step explanation:
A boiler horsepower (BHP) is a unit of measurement used to describe the power output of a boiler. It is defined as 1 BHP being equivalent to 33,475 BTU per hour. Therefore, the correct option for the definition of a boiler horsepower (BHP) is b) boiler BTU input / 676,000.