A 10-meter-long spear is thrown at a relativistic speed through a 10-meter-long pipe (both measured when at rest.) when the spear passes through the pipe,
a. the pipe shrinks so the spear extends at both ends.
b. both shrink equally so the pipe barely covers the spear.
c. the spear shrinks so the pipe completely covers it.
d. any of the above, depending on the motion of the observer
e. none of the above