The correct answer is A. haematite.
Haematite is the most common type of iron ore. It is a red ore that is found in both igneous and sedimentary rocks. Haematite is an important source of iron, and it is used to make steel.
Siderite is a type of iron ore that is found in sedimentary rocks. It is a black ore that is composed of iron carbonate. Siderite is not as common as haematite, but it is still an important source of iron.
Limonite is a type of iron ore that is found in both igneous and sedimentary rocks. It is a brown ore that is composed of iron oxide and hydroxide. Limonite is not as common as haematite or siderite, but it is still an important source of iron.
Magnetite is a type of iron ore that is found in igneous rocks. It is a black ore that is composed of iron oxide. Magnetite is a very important source of iron, and it is used to make steel.
In conclusion, the iron ore mined at Bailadila is mostly haematite. Haematite is the most common type of iron ore, and it is an important source of iron.