The answer is B. Germanium.
Magnalium, duralumin, bronze, and brass are all alloys, which are mixtures of metals. Germanium is a chemical element.
Magnalium is an alloy of aluminum and magnesium. It is strong and lightweight, and is used in aircraft construction, automotive parts, and other applications where strength and lightness are important.
Duralumin is an alloy of aluminum, copper, manganese, and silicon. It is strong and lightweight, and is used in aircraft construction, automotive parts, and other applications where strength and lightness are important.
Bronze is an alloy of copper and tin. It is strong and durable, and is used in sculptures, coins, and other applications where strength and durability are important.
Brass is an alloy of copper and zinc. It is strong and corrosion-resistant, and is used in plumbing fixtures, musical instruments, and other applications where strength and corrosion resistance are important.
Germanium is a chemical element with the symbol Ge and atomic number 32. It is a metalloid in the carbon group in the periodic table. It is a silvery-white metalloid that is chemically similar to silicon and tin. It is a semiconductor and is used in transistors, solar cells, and other electronic devices.