When we call an attack a $$zero day exploit,$$ we mean that: This type of question contains radio buttons and checkboxes for selection of options. Use Tab for navigation and Enter or space to select the option. option A This term is meaningless hyperbole, invented by the popular press. option B The attack exploited a vulnerability within the first $24$ hours of its being announced by the affected systems or software vendor, or when it was posted in the CVE. option C The attack exploited a vulnerability within the first $24$ hours of its discovery. option D The attack exploited a previously unreported vulnerability before the affected systems or software vendor recognized and acknowledged it$,$ reported or disclosed it$,$ or provided a warning to its customers.