In the arrangement shown in figure, the current through 5Ω resistor is?

Correct option is A. 2A
In this circuit there are 2 cells connected in parallel.
Equivalent internal resistance, req = (r1 + r2)/(r1 * r2) where r1 and r2 are the respective internal resistance.
Hence req = 1Ω
And Equivalent e.m.f, Eeq = (E1r1 + E2r2)/(r1 + r2)
Hence on solving we get Eeq = 12V
Hence current through 5Ω resistor
I = Eeq/(req + 5) = 12/(1 + 5) = 2A