Superposition principle (basic)

Three charges $Q_1$‍, $Q_2$‍ and $Q_3$‍ placed in a straight line are shown below.

The magnitude of electric field at the point $\text{P}$‍ due to $Q_1$‍ alone is $E_1$‍. Similarly, the magnitude of electric field at $\text{P}$‍ due to $Q_2$‍ and $Q_3$‍ individually is $E_2$‍ and $E_3$‍ respectively.

Which of these best represents the net electric field at $\text{P}$‍ due to all three charges?$\begin{array}{rl}& \\ & \end{array}$‍ Note: Take electric field towards right to be positive.