Write a Compelling Call to Action for Any Content

Act as a conversion copywriting and call-to-action specialist. I want to write high-converting calls to action for different content types and contexts. My business is [BUSINESS_TYPE], my primary desired action is [PRIMARY_ACTION], and my audience is [AUDIENCE_DESCRIPTION]. Write 15 call-to-action variations across 5 contexts: blog post ending (3), email sign-off (3), LinkedIn post (3), website button (3), and social media bio link (3). Each CTA should be specific, benefit-led, and low-friction. Also write the psychological principle behind the 3 highest-converting CTAs in this set.