AIIMS 2018 Physics Electric Field Assertion Reason Question

Option A is correct because the assertion accurately states that the electric field (E) due to an infinitely long straight uniformly charged wire decreases as the distance (r) from the wire increases, specifically following the relationship $E \propto \frac{1}{r}$. When the distance is doubled, the electric field indeed reduces to one third of its initial value, confirming that the reason provided correctly explains the assertion.

Option B is incorrect because the reason does explain the assertion. Option C is incorrect as both the assertion and reason are true. Option D is incorrect since both statements are valid in the context of electrostatics.