Answer: option A
Explanation:
Three main types of Chemical bonds are ionic, covalent bond and metallic bond.
Ionic bond: If Electronegativity difference is>1.7 and formed between metal and non metal. Example,NaCl
Covalent: Electronegativity difference is <1.7 and bonded electrons shared by bonded atoms equally. Observed between non metals
Example, CH4,H2O
Metallic bond: Observed in metallic elements like Na,Cu and Fe etc.
