In surgery, metal pins are used for joining together broken bones. These metal pins remain uncorroded in the body. What is the material of these pins? A. Copper B. Iron C. Aluminium D. Titanium

The correct answer is D. Titanium.

Titanium is a strong, lightweight metal that is resistant to corrosion. It is often used in medical implants, such as pins used to join together broken bones. Titanium is also used in aircraft and other applications where strength and corrosion resistance are important.

Copper is a soft, malleable metal that is not as strong as titanium. It is also more susceptible to corrosion. Iron is a strong metal, but it is also more susceptible to corrosion than titanium. Aluminium is a lightweight metal that is not as strong as titanium. It is also more susceptible to corrosion than titanium.

In conclusion, titanium is the best material for metal pins used in surgery because it is strong, lightweight, and resistant to corrosion.