Consider the following statements regarding impedance matching:
1. When the line is terminated in an impedance other than its characteristic impedance, reflection will occur and there will be standing waves of voltage and current along the line which may be very large if there is considerable mismatch.
2. The single-stub device has the advantage that it will match any load.
3. The double stub has the disadvantage that the line length needs to be adjustable.
Which of the above statements are correct?

A. 2 and 3 only

B. 1 and 2 only

C. 1 and 3 only

D. 1, 2 and 3

Answer: Option D