In the context of the input sentence, determine the relationship between 'MedImmune' and 'AstraZeneca'.
Options: parent organization, manufacturer, platform, original broadcaster

Companies like Pfizer, Sanofi, Merck, AstraZeneca and MedImmune continue to disinfect with a safe SteraMist BIT chemical protecting their operator, facility and the environment, while providing the confidence to the American population that we will produce sterile vaccines.
parent organization