An electromagnetic wave of the same frequency travels successively through the following media:
(i) vacuum (n=1.0),
(ii) water (n=1.33),
(iii) crown glass (n=1.50),
(iv) flint glass (n=1.80).
Which one of the following correctly ranks the wavelengths λ of the wave in these media from longest to shortest?
a) flint\,glass > crown\,glass > water > vacuum
b) vacuum > crown\,glass > water > flint\,glass
c) vacuum > water > crown\,glass > flint\,glass
d) water > vacuum > crown\,glass > flint\,glass