The Tesla (T) is the SI unit of magnetic flux density (or magnetic field strength).
It is defined as: $$1 \text{ Tesla (T)} = 1 \frac{\text{Weber}}{\text{meter}^2} = 1 \frac{\text{Wb}}{\text{m}^2}$$
So the correct answer is (3).
A metallic ring is uniformly charged as shown in the figure. AC and BD are two mutually perpendicular diameters. Electric field due to arc AB to O is ‘E’ magnitude. What would be the magnitude of electric field at ‘O’ due to arc ABC?