Silicon is an example of 

Solution

Metals like Na and Mg are towards the left-hand side of the Periodic Table while the non-metals like sulphur and chlorine are found on the right-hand side. In the middle, we have silicon, which is classified as a semi-metal or metalloid because it exhibits some properties of both metals and non-metals. In the Periodic Table, it is depicted by a zig-zag line. Some other examples of metalloids are boron, arsenic, antimony, tellurium etc. Hence, option C is correct.