Answer
Tension , T = w /$\sqrt 2$
That is , option 2
Work Step by Step
Let T be the Tension in each string
Since , traffic light and lightweight cables are in translational equilibrium
Therefore , applying newton's law of motion in horizontal direction we get ,
Tsin45$^{\circ}$ + Tsin45$^{\circ}$ = mg
2Tsin45$^{\circ}$ = mg
2T(1/$\sqrt 2$) = mg (Since , sin45$^{\circ}$ = 1/$\sqrt 2$)
T = mg/$\sqrt 2$
According to question , mg = w
Therefore , T = w/$\sqrt 2$
