Concept:The underlined letters "ch" in "chunk" represent the consonant sound /tʃ/.Explanation:"chunk" is pronounced /tʃʌŋk/.The correct option must also contain the sound /tʃ/.A. "choir" is pronounced /ˈkwaɪə/ — it does not contain /tʃ/.B. "chemise" is pronounced /ʃɪˈmiːz/ — it contains /ʃ/, not /tʃ/.C. "matches" is pronounced /ˈmætʃɪz/ — it contains the same /tʃ/ sound.D. "show" is pronounced /ʃoʊ/ — it contains /ʃ/, not /tʃ/.Answer:C. matches