A. C, and D here. Building advocates means going beyond just transactional point earning (so B's mostly a trap). You need targeted promos (A), engagement through tiers (C), and rewarding advocacy actions like social sharing (D). I'm pretty sure that's what Salesforce wants for true advocacy, but open if anyone sees it differently.
Had something like this in a mock, pretty sure it's A, C, and D. Tiered benefits and targeted promos (A, C) plus rewarding social advocacy (D) are all about creating advocates. Let me know if you see it differently.
I don't think B fits here. The question's about building advocacy, not just earning points for spending. A, C, and D help target and engage members beyond basic transactions. The tier benefit in C is what sets advocates apart from regular users.