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A particle having a mass of carries a charge of  The particle is given an initial horizontal velocity of  in the presence of electric field $\stackrel{\to }{\mathbf{E}}$ and magnetic field $\stackrel{\to }{\mathbf{B}}$. To keep the particle moving in a horizontal direction, it is necessary that

(1) $\stackrel{\to }{\mathbf{B}}$ should be perpendicular to the direction of velocity and $\stackrel{\to }{\mathbf{E}}$ should be along the direction of velocity.

(2) Both $\stackrel{\to }{\mathbf{B}}$ and $\stackrel{\to }{\mathbf{E}}$ should be along the direction of velocity.

(3) Both $\stackrel{\to }{\mathbf{B}}$ and $\stackrel{\to }{\mathbf{E}}$ are mutually perpendicular and perpendicular to the direction of velocity.

(4) $\stackrel{\to }{\mathbf{B}}$ should be along the direction of velocity and $\stackrel{\to }{\mathbf{E}}$ should be perpendicular to the direction of velocity.

Which one of the following pairs of statements are possible?

(a)   (1) and (3)                                       (b)    (3) and (4)

(c)   (2) and (3)                                        (d)   (2) and (4)

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