The alloying element which can replace tungsten in high speed steels is

Answer: Option D

Molybdenum has effects similar to manganese and vanadium, and is often used in combination with one or the other.
This element is a strong carbide former and is usually present in alloy steels in amounts less than 1%.
It increases hardenability and elevated temperature strength and also improves corrosion resistance as well as increased creep strength.
It is added to stainless steels to increase their resistance to corrosion and is also used in high speed tool steels.