11.B-rated firms have been observed to have probability of default of 1.9， 3.4 and 5.8 percent during years 1， 2， and 3 from present. The probability that a B-rated firm will default within the next three years is CLOSEST to：
　　A. 3.71%.
　　B. 9.00%.
　　C. 10.73%.
　　D. 11.10%.
　　Correct answer：C
　　12.Based on historical data from Moody‘s， the 1-year default probability for B-rated firms is CLOSEST to：
　　A. 0.1%.
　　B. 0.3%.
　　C. 1.4%.
　　D. 4.5%.
　　Correct answer：D
　　13.The position of a lender is most similar to a：
　　A. long put.
　　B. long call.
　　C. short put.
　　D. short call.
　　Correct answer：C
　　14.A portfolio consists of ten A-rated bonds that have a one-year default probability of 1.12% and no correlation between them. What is the probability that the portfolio will suffer no loss over this period？
　　A. 89%.
　　B. 91%.
　　C. 93%.
　　D. 95%.
　　Correct answer：A
　　15.The ratio of the default probability of an A-rated issuer over the default probability of a AAArated issuer generally：
　　A. remains constant over time.
　　B. increases with the time horizon.
　　C. decreases with the time horizon.
　　D. may increase or decrease depending on the given industrial sector.
　　Correct answer：C