Electric field lines:

Solution

Physics sir · 3 steps

At any point the field has one direction only, so two lines can never cross there.

1. What a line shows. The tangent to a field line at a point gives the direction of the electric field E⃗ at that point. So every field line carries a direction, shown by an arrow.
2. Why no crossing. If two lines crossed, the point of crossing would have two tangents, so E⃗ would point two ways at once. The field at a point is a single vector, so this is impossible.

   Option	Check	Verdict
   (a) start from negative charges	Lines start on positive charges and end on negative charges	false
   (b) always form closed loops	Electrostatic field lines begin and end on charges, so they never close on themselves	false
   (c) never intersect	One point has only one field direction	true
   (d) have no direction	Each line points along E⃗, from + to −	false

3. So. The correct property is (c): electric field lines never intersect each other.

The idea to keep. A field line's tangent is the field's direction. One point, one direction, so field lines never cross. Electrostatic lines run from positive to negative charge and never form closed loops.

Answer from the NTA final answer key. Solution by PrepWiser.