Concept:The symbol /ŋ/ is the voiced velar nasal sound, often written as "ng" or "nk".
Explanation:In the word "sink", the letters "nk" together produce the /ŋk/ sound.
Therefore, "sink" clearly contains the /ŋ/ sound.
"Thin" ends with an /n/ sound, not /ŋ/.
"Hinge" contains the /ndʒ/ sound, not /ŋ/.
"Reign" is pronounced with a silent "g", so it has only /n/.
Hence, the correct option is "sink".
Answer:B. sink