The correct answer is (d) Hematite.
Hematite is the most abundant and important iron ore. It is a mineral that is composed of iron oxide, and it is found in a variety of colors, including red, brown, and black. Hematite is an important ore because it is a major source of iron, which is used in a variety of industries, including steelmaking.
Siderite is a mineral that is composed of iron carbonate. It is a relatively common mineral, but it is not as important as hematite because it contains less iron. Limonite is a mineral that is composed of iron oxide and hydroxide. It is a common mineral, but it is not as important as hematite or siderite because it contains less iron. Magnetite is a mineral that is composed of iron oxide. It is a relatively common mineral, and it is an important ore because it contains a high percentage of iron. However, it is not as important as hematite because it is more difficult to extract the iron from magnetite.
In conclusion, hematite is the best quality of iron ore because it contains the most iron and is the easiest to extract.