Explanation

The correct answer is A. I-spread.

Understanding the Spread Types:

1. I-spread (Interpolated Spread or ISDA Spread): This is the yield spread of a bond over the standard swap rate for the same currency and tenor. It represents the difference between the bond's yield and the swap rate curve.

2. G-spread (Government Spread): This is the yield spread of a bond over a government bond of similar maturity. It measures the credit risk premium relative to the risk-free government benchmark.

3. Z-spread (Zero-volatility Spread): This is the constant spread that must be added to each spot rate on the Treasury spot curve to make the present value of a bond's cash flows equal to its market price. It accounts for the shape of the yield curve.

Key Distinction:

• I-spread specifically refers to the spread over the swap rate curve
• G-spread refers to the spread over government bond yields
• Z-spread is a more complex measure that accounts for the entire yield curve shape

Why I-spread is Correct:

The question explicitly asks for "a bond's yield spread over the standard swap rate." This is the precise definition of the I-spread. The swap rate serves as a benchmark for corporate funding costs, and the I-spread measures how much additional yield investors demand to hold a bond instead of entering into a swap agreement.

Additional Context:

• Swap rates are often used as benchmarks because they represent the cost of funding for financial institutions
• The I-spread is particularly useful for comparing bonds to the swap market, which is often more liquid than the government bond market
• This spread helps investors assess the relative value of bonds compared to the swap curve