The correct option is C.
Both DNA and RNA are made up of four nitrogenous bases. The nitrogenous bases that are found in DNA are adenine, guanine, cytosine and thymine. The nitrogenous bases that are found in RNA are adenine, guanine, cytosine and uracil.
The atomic number is 5. The atomic number gives the number of protons. Protons which have a positive charge are balanced by an equal number of electrons in a neutral atom. Boron number 5 has five protons and therefore as a neutral atom also has five electrons. Boron atomic number 5 has five electrons in its ground state. Commonly Boron will lose 3 electrons leaving 2 electrons in its most common ionic form.