How many number of neutrons are there in tritium?

The correct option is B Two
Trituim is the isotope of hydrogen with symbol $H_1^3$.

The atomic number of tritium is one and the mass number is three. The number of neutrons is equal to the difference between the mass number of the atom (M) and the atomic number (Z).

Therefore, the number of neutrons present in tritium $=3-1=2$.