The correct answer is (b) Si. Quartz is a silicon dioxide mineral with the chemical formula SiO2. It is a hard, brittle, and transparent solid that is found in nature as well as produced synthetically. Quartz is used in a variety of applications, including electronics, optics, and jewelry. It is also used as a piezoelectric material, which means that it can generate an electric charge when it is subjected to mechanical stress. This property makes quartz useful in devices such as oscillators, filters, and sensors.
The other options are incorrect. Mercury (Hg) is a liquid metal that is used in thermometers, barometers, and other scientific instruments. Titanium (Ti) is a strong, lightweight metal that is used in aircraft, engines, and other applications. Tin (Sn) is a soft, silvery-white metal that is used in solder, cans, and other products.