Boilers classification: identify the correct combined statement about common boiler types Check each named boiler against its family (fire-tube or water-tube) and firing arrangement. Choose the correct option.

Given facts
• Lancashire is a classic fire-tube boiler with two large furnace/flue tubes.
• Typical fire-tube units (Cornish, Lancashire, locomotive, Scotch marine) are internally fired (furnace within the shell).
• Babcock & Wilcox is a water-tube boiler (water/steam in tubes, hot gases outside).

Concept/Approach
Identify each boiler type by where the water/steam flows and where the furnace is placed.

Result
All three statements (a), (b), and (c) are correct, so the best choice is all of the above.