# In a gas discharge tube, the total electric charge flowing per second due to the positive ions is $Q_2\; C$ and due to electrons is $−Q_2\; C$. What is the net electric current flowing in the tube?

$\begin{array}{1 1}(A)\;(Q_2 -Q_2) \;A\\ (B)\;(Q_2 +Q_2)\;A \\ (C)\;(Q_2/Q_2)\;A \\(D)\;(Q_2 /Q_2)\;A \end{array}$

$(Q_2 +Q_2)\;A$is the net electric current flowing in the tube
Hence B is the correct answer.