Which of the following elements has the chemical symbol Pb?

The element with the chemical symbol Pb is lead. This designation comes from the Latin name for lead, which is "plumbum." In the context of the periodic table, lead is classified as a post-transition metal and has several important applications, including usage in batteries, radiation shielding, and soldering materials, due to its dense and malleable nature.

The other elements listed do not share this symbol. Tin is represented by the symbol Sn, derived from its Latin name "stannum." Silicon, used extensively in electronics and computer technology, is denoted by the symbol Si, while nitrogen, an essential element for life and a key component of the Earth's atmosphere, has the symbol N. Each of these elements has distinct properties and applications, setting them apart from lead.