A particle moves with deceleration along the circle of radius R so that at any moment of time its tangential and normal acceleration are equal in moduli. At the initial moment t =0 the speed of the particle equals `v_o`, then the speed of the particle as a function of the distance covered s will be
| A. |
`v=v_0e^(-S/R)` |
 |
| B. |
`v=v_0e^(S/R)` |
| C. |
`v=v_0e^(-R/S)` |
| D. |
`v=v_0e^(R/S)` |