The given diagram shows isotherms for a fixed mass of an ideal gas at temperature `T_1` and `T_2`. What is the value of the ratio
`(text(r.m.s. speed of the molecules at temperature) T_2)/(text(r.m.s. speed of the molecules at temperature) T_1)` ?
| A. |
`sqrt2` |
| B. |
2 |
 |
| C. |
`2sqrt2` |
| D. |
4 |