What should Siobhan do after receiving a parking ticket?

Paying the parking ticket is the most appropriate action for Siobhan to take after receiving it. When a parking ticket is issued, it usually indicates a violation of parking regulations that requires immediate attention to avoid further penalties, such as additional fines or legal action. Taking care of the ticket promptly demonstrates responsibility and compliance with local laws.

Informing (ISC)², supervisors at Triffid, or resigning from employment are not necessary steps to take in this context, as they do not address the immediate issue of the parking violation. The focus should remain on resolving the ticket itself, which is rooted in maintaining good standing with local authorities and avoiding any escalation of the situation.