If you don’t have a skill on their list, don’t pretend you do and don’t try to deny it. Instead, use your resume to highlight the attributes you do possess.
For instance, if the position calls for public relations experience at an agency and you don’t have that, focus on how you’ve organically grown your own social media following and landed media placements on your own. Or if the job requires working knowledge of a specific program or software that you don’t have, stress a similar one you do possess and talk about how quickly you pick up new skills and how you value training.
Shift the discussion and focus to your strengths instead of inadvertently accentuating your weaknesses.