Why are halogens strong oxidising agents?

(N/A) The general electronic configuration of halogens is $ns^2 np^5$.
They require only one electron to complete their octet and attain the stable noble gas configuration.
Halogens possess high electronegativity,low dissociation energies,and high negative electron gain enthalpies.
Due to these factors,they have a strong tendency to gain an electron,which makes them strong oxidizing agents.