Concept:The underlined letters "ss" in "fissure" are pronounced /ʃ/, the same sound as "sh" in "ship."
We should select the option that has this exact consonant sound, not a similar voiced sound.
Explanation:"Fissure" is pronounced /ˈfɪʃə/, so the letters "ss" give the voiceless "sh" sound /ʃ/.
Option A, "unsure", is pronounced /ʌnˈʃɔː/ or /ʌnˈʃʊə/. The "s" in "sure" is pronounced /ʃ/, so it matches exactly.
Option B, "feature", has /tʃ/ in "ture"; this is a "ch" sound, not a pure "sh" sound.
Option C, "erase", has /s/ or /z/ depending on pronunciation, not /ʃ/.
Option D, "vision", has the voiced sound /ʒ/ in "sion", not the voiceless /ʃ/ sound we need.
Therefore, the correct word is "unsure."
Answer:A. unsure