An infinitely long uniform solid wire of radius a carries uniform dc current of density $$\overrightarrow {\text{J}} .$$
The magnetic field at a distance r from the center of the wire is proportional to

A. r for r < a and $$\frac{1}{{{{\text{r}}^2}}}$$ for r > a

B. 0 for r < a and $$\frac{1}{{\text{r}}}$$ for r > a

C. r for r < a and $$\frac{1}{{\text{r}}}$$ for r > a

D. 0 for r < a and $$\frac{1}{{{{\text{r}}^2}}}$$ for r > a

Answer: Option C