B
Explanation:
The electric field strength direction is the same as the direction of the electric force.
The electric field will be directed out of the rod in all directions, as it contains uniformly distributed positive charges.
Getting the vector sum for the electric field, due to symmetry the total electric field strength will be directed out of the rod with an angle away from the midpoint of the rod as shown
Also we can think of B as the only correct solution, because it’s a positively charged rod, so the direction must be out of the rod.