An investment bank offers to sell you a credit linked note where the interest rate is higher than the risk-free rate. The downside is that you might not get back all your capital if Rio Tinto defaults. To replicate this strategy I could:

a. short a bond issued by Rio Tinto and long a risk-free bond.

b. long a bond issued by Rio Tinto and short a risk-free bond.

c. long a risk-free bond and short a CDS over Rio Tinto.

d. long a risk-free bond and long a CDS over Rio Tinto.