challenge: According to critics, what was a key characteristic of some MIS investments by Great Southern Group that resembled a problematic financial scheme?
  
  A. They relied on attracting new investors to secure financial returns for existing investors, rather than on successful economic activity.
  B. They were immune to economic circumstances and investor uncertainty.
  C. They were backed by successful economic activity and generated returns through profitable commodity production.
  D. They were underpinned by low levels of debt and focused on selling the tax benefits of investments.
  Answer: 