(c) At OK, semiconductor behaves as an insulator, hence, there is no free electrons in the semiconductor at 0K. At room temperature or above room temperature, some covalent bonds are broken, hence some free electrons are found at these temperatures. On increasing temperature, more number of covalent bonds are broken, hence number of free electrons increases with increase of temperature of semiconductor. Conductivity of semiconductor is less than that in conductor, hence number of free electrons in semiconductor is less than that of conductor. Therefore, statements (A), (C), (D) are correct but (B) is false.