A signal e-at sin ( t) is the input to a real linear time-invariant system. Given K and are constants, the output of the system will be of the form Ke-bt sin (vt + ). The correct statement among the following is __________

• A. b need not be equal to a but v must be equal to
• B. v need not be equal to but b must be equal to a
• C. b must be equal to a and v must be equal to
• D. b need not be equal to a and v need not be equal to