Stacey, a lawyer, earns a very high income and owns a home with a $250,000 mortgage at 5%. She has $45,000 in RRSP contribution room. Her marginal tax rate is 50%. She asks you how she can make the best use of her $20,000 bonus from work. Which of the following options are you most likely to recommend? 

 Make a lump sum payment of $20,000 on her mortgage loan. 

Deposit $20,000 in a non-registered investment. 

Contribute $10,000 to her RRSP and make a lump sum payment of $10,000 on her mortgage loan. 

Contribute $20,000 to her RRSP.