Effect of steam on thermal resistance of insulated pipe exposed in air?

Question

 A pipe carrying saturated steam is converged with a layer of insulation and exposed to ambient air. The thermal resistances are as shown in the following figure.                                           (IES-96)

Which one of the following statements is correct in this regard.

1. R_steam and R_pipe negligible as compared to R_ins and R_air
2. R_pipe and R_air negligible as compared to R_ins and R_steam
3. R_steam and R_air negligible as compared to R_pipe and R_ins
4. No equantitative data is provided, therefore no comparision is possible.