23. Spaceship A and spaceship B are travelling in constant speed but in the opposite direction. The observer on spaceship B has found the length of spaceship A is slightly longer than the length of spaceship B. Afterwards the spaceship B has doubled its speed. Which of the following statements has the chance to be true?
(A) After speed up, the length of spaceship A can be shorter than the length of spaceship B for the same observer on spaceship B.
(B) After speed up, the length of spaceship A can be shorter than the length of spaceship B from another observer on spaceship A.
(C) If spaceship B changed its flight direction to the opposite but with the same speed at the beginning, the length of spaceship A can be shorter than the length of spaceship B from the observer on spaceship A.
(D) If both spaceships are at rest, they can have the same length.