Covalent bonding is found in which of the following compounds?

Covalent bonds are defined as the sharing of electrons between atoms.

In molecules containing methane, covalent bonds exist. One carbon atom must combine with four hydrogen atoms to form a methane molecule. All hydrogen atoms only have one electron in their outermost shell, compared to carbon's four electrons.

A  carbon atom shares four electrons with each of its hydrogen atoms. Carbon has a complete octet, compared to all four hydrogen atoms having a complete duplet.

$\mathrm{NaCl}, \mathrm{HCl}$and $\mathrm{NaOH}$forms ionic bond.