A suffix is a morpheme or words added at the end of the word to form a new word or change the meaning of the word.
Example, with the suffix -etic (means relating to), an athlete is changed into athletic and energy is changed into energetic which changes the meaning of the word.
Hence, suffix which can be added to create a word 'phon' meaning "having characteristics of sound" is '-ic - Phonic'. phonic refers to sounding of the words for the beginners.
