Thomas slag is
Explanation for correct option:
Option B.
Thomas slag:
Explanation for incorrect options:
Option A. Wollastonite is mineral composed of calcium inosilicate mineral that may contain small amounts of iron, magnesium, and manganese substituting for calcium.
Option C. Calcium carbonate has a molecular formula that is found in the mineral rock known as calcite. It is also known as limestone.
Option D. is a low-temperature high-pressure, dimorph of rhodonite and is known as Pyroxmangite.
Hence, the correct option is B. Thomas slag is .