Because of Heisenberg's Uncertainty Principle, the Velocity of a Particle

Multiple Choice

Because of Heisenberg's Uncertainty Principle, the velocity of a particle is known least precisely when the length of the wave packet representing the particle is:

A) < 10^-15 m.
B) < 10^-10 m.
C) of the order of 1.00 m.
D) >10 m.
E) the length of a plane wave (infinite)