A charged object is launched inside a time varying electric field. Its motion is recorded by a video camera on a video tape. When it is at a certain moment $A$ , its position vector $\vec r$, velocity $\vec v$ and acceleration $\vec a$ are measured. A student watches the video at a later time but mistakenly plays the tape in the reverse direction. What is the position, velocity, and acceleration of the object, at moment $A$ observed by the student respectively?

  • A

    $\vec r,\vec v,\vec a$

  • B

    $- \vec r, -\vec v, -\vec a$

  • C

    $\vec r,- \vec v,\vec a$

  • D

    $\vec r,\vec v,- \vec a$

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