The Poynting vector of electromagnetic waves has the same dimensions as that of:

Correct option is C

​$$\text{Dimensions of the Poynting vector:} \\[6pt]\text{It has units of power per unit area, i.e., energy flow per second per unit area:} \\[12pt][\mathbf{S}] = \frac{\text{Watts}}{\text{meter}^2} = \frac{\text{Joule}}{\text{second} \cdot \text{meter}^2} = \frac{\text{Energy}}{\text{time} \times \text{area}}$$

Power density is power per unit area, the same dimension as the Poynting vector.​​