Match the following columns :

	Column-I		Column-II
a)	${\mathrm{NH}}_3\cdot {\mathrm{BF}}_3$	p)	Ionic bond
b)	$\mathrm{CO}$	q)	Covalent bond
c)	${\mathrm{NH}}_4\mathrm{Cl}$	r)	Co-ordinate bond
d)	${\mathrm{KI}}_3$	s)	3 lone pair on any one atom

The triple bond between C and O in CO. Two of these three bonds—the covalent bonds—are created by the sharing of electrons between carbon and oxygen. Covalent and coordinate bonds are present.
An iodine atom joins an iodine molecule in the KI₃ molecule through a coordinate covalent link. Consequently, the O.N. of the two I atoms that make up the I₂ molecule in a KI₃ molecule is 0.
The trivalent binding between N and H⁺ions, the dative bond between N and H⁺ions, and the ionic bond between ammonium ions and chloride ions make up NH₄Cl.

Thus the option B is correct.