Which of the following pair of expressions for drift velocity `v_d` is correct?

Options

A. `v_d = (eE)/m tau and v_d = I/(nAe)`
B. `v_d = (eE)/m tau and v_d = IR`
C. `v_d = (- eE)/m tau and v_d = J/(nAe)`
D. `v_d = ( - e^2 E)/m tau and v_d = 1/(n^2 Ae)`

Answer

A