Wraparound deed of trust

A Wraparound deed of trust:

  1.  Allows the seller to retain title.
  2.  Is illegal
  3.  Can be used to refinance a property.
  4.  Make the due-on-sale clause unenforceable.

The answer is C.  A wraparound deed of trust is legal, would transfer title to the buyer, and a due-on-sale clause would still be enforceable, which means that the bank can call the entire mortgage due and payable.