Identify the correct statement from the following.

Tritium is an isotope of

Assertion : Hydrogen combines with other elements by losing,gaining or sharing of electrons.
Reason : Hydrogen forms electrovalent and covalent bonds with other elements.

Name the classes of hydrides to which $H_2O$,$B_2H_6$ and $NaH$ belong.

Consider the following statements and identify which of them are correct:
$I.$ Atomic hydrogen is obtained by applying an electric arc to hydrogen gas.
$II.$ Hydrogen gas does not reduce heated aluminum.
$III.$ Finely divided palladium absorbs a large volume of hydrogen gas.
$IV.$ The reaction of $Na$ with $C_2H_5OH$ yields pure nascent hydrogen.

What is Carbogen?