The correct sequence of the radiation source in increasing order of the wavelength is Radioactive source $\left(\sim 10^{-12} \mathrm{~m}\right) \rightarrow$ X-ray tube $\left(\sim 10^{-10} \mathrm{~m}\right) \rightarrow$ Sodium lamp $\left(\sim 10^{-9} \mathrm{~m}\right) \rightarrow$ Magnetron value $\left(\sim 10^{-3} \mathrm{~m}\right)$.