An investor gathered the following information about two 7 percent annual-pay, option-free bonds: Bond R has 4 years to maturity and is priced to yield 6 percent Bond S has 7 years to maturity and is priced to yield 6 percent Both bonds have a par value of $1000. Given a 50 basis point parallel upward shift in interest rates, what is the value of the two-bond portfolio（）
A. $2044.
B. $2030.
C. $2086.
