🔍 Key Concepts

• Boiler furnace location and function in an oil‑fired boiler • Difference between a mud drum and water drum (where they are placed and what they contain) • How the burner and flame are positioned relative to the furnace and drums in typical boiler diagrams

💭 Think About

• Look at what is happening inside the area marked C: is it mainly a space for combustion, or a drum for collecting water/steam? • Trace where the burner is located and where the hot gases first enter the boiler—does C match that location? • Compare the shapes: does C look like a cylindrical drum on the water side of the system, or more like an open chamber beneath/around the tubes?

✅ Before You Answer

• Identify where combustion is clearly shown in the illustration (flame, burner, combustion space) and see which label it aligns with • Check whether C is connected to the water/steam circulation like a drum, or only exposed to hot gases • Confirm the usual position of a mud drum (low point collecting sludge) versus the furnace (combustion chamber) in standard marine boiler layouts before selecting your choice