Which of the following should be the FIRST sentence after rearrangement?

Directions: Rearrange the following five sentences in the proper sequence to form a coherent paragraph, and then answer the question given below. 

(1)     Again, the higher languages are written and are thus, immediately accessible.
(2)     For such reasons, chief attention has been given to the most highly developed languages.
(3)     As the progress of research is necessarily from the known to the unknown, civilized languages were studied by scholars before the languages of savage and barbaric tribes.
(4)     However, the problems presented to the philologist, in the higher languages, cannot be properly solved without a knowledge of the lower forms.
(5)     In philology, North America presents the richest field in the world, for here is found the greatest number of languages distributed among the greatest number of stocks.