An alloy steel which is work hardenable and which is used to make the blades of bulldozers, bucket wheel excavators and other earth moving equipment contain iron, carbon and

Answer: Option C

Manganese increases hardenability and tensile strength of steel, but to a lesser extent than carbon.
It is also able to decrease the critical cooling rate during hardening, thus increasing the steels hardenability much more efficient than any other alloying elements.
Manganese is used to make the blades of bulldozers, bucket wheel excavators and other earth moving equipment contain iron.