You cannot answer this question without knowing what kind of accent the author of the exercise expects you to be using and what transcription system the book uses.

As I explain in my answer to Pronunciation of -ies, like the last syllable of "accessories" and "bees" in BrE, the final syllable of words like taxi and ferry could be transcribed as /i/, /ɪ/ or /iː/ depending on various considerations. For some accents, /ɪ/ is clearly inappropriate; for other accents, /iː/ is clearly inappropriate. The transcription /i/ is often used as a kind of "compromise", but it confusingly suggests the presence of three distinct "[i]-like" vowel sounds, when really most speakers will probably only think of there being two.

The tricky part is that speakers of different accents disagree about which of the two vowel sounds is present at the end of words like taxi. This isn't simple matter of one type of accent being British English, and the other being American English. Pronouncing "ferry" with /ɪ/ is probably very uncommon now in American English, but pronouncing "ferry" with "/iː/" is not uncommon in British English.

It seems like a badly written question. Because length markers are a somewhat common source of confusion, some phoneticians have suggested not using them in transcriptions for foreign learners of English.

As I explain in my answer to Pronunciation of -ies, like the last syllable of "accessories" and "bees" in BrE, the final syllable of words like taxi and ferry could be transcribed as /i/, /ɪ/ or /iː/ depending on various considerations. For some accents, /ɪ/ is clearly inappropriate; for other accents, /iː/ is clearly inappropriate. The transcription /i/ is often used as a kind of "compromise", but it confusingly suggests the presence of three distinct "[i]-like" vowel sounds, when really most speakers will probably only think of there being two.

The tricky part is that speakers of different accents disagree about which of the two vowel sounds is present at the end of words like taxi. This isn't simple matter of one type of accent being British English, and the other being American English. Pronouncing "ferry" with /ɪ/ is probably very uncommon now in American English, but pronouncing "ferry" with "/iː/" is not uncommon in British English.

In word-final position, there is no real contrast between /i/ and /iː/, unless we ignore stress and transcribe unstressed /iː/ as /i/. That is, we could have a contrast like /ˈtæksi/ "taxi" vs. /ˈtakˌsi/ "tack-see". But the same kind of contrast could exist with any other vowel in the second syllable: for example, "crypto" /ˈkrɪptoʊ/ vs. "tiptoe" /ˈtɪpˌtoʊ/.

It seems like a badly written question. Because length markers are a somewhat common source of confusion, some phoneticians have suggested not using them in transcriptions for foreign learners of English.

You cannot answer this question without knowing what kind of accent the author of the exercise expects you to be using and what transcription system the book uses.

As I explain in my answer to Pronunciation of -ies, like the last syllable of "accessories" and "bees" in BrE, the final syllable of words like taxi and ferry could be transcribed as /i/, /ɪ/ or /iː/ depending on various considerations. For some accents, /ɪ/ is clearly inappropriate; for other accents, /iː/ is clearly inappropriate. The transcription /i/ is often used as a kind of "compromise", but it confusingly suggests the presence of three distinct "[i]-like" vowel sounds, when really most speakers will probably only think of there being two. (The tricky part is that speakers of different accents disagree about which of the two vowel sounds is present at the end of words like taxi.)

It seems like a badly written question, but there might be context in the part that you haven't shown us that makes it clearer how they expect you to answer.

You cannot answer this question without knowing what kind of accent the author of the exercise expects you to be using and what transcription system the book uses.

As I explain in my answer to Pronunciation of -ies, like the last syllable of "accessories" and "bees" in BrE, the final syllable of words like taxi and ferry could be transcribed as /i/, /ɪ/ or /iː/ depending on various considerations. For some accents, /ɪ/ is clearly inappropriate; for other accents, /iː/ is clearly inappropriate. The transcription /i/ is often used as a kind of "compromise", but it confusingly suggests the presence of three distinct "[i]-like" vowel sounds, when really most speakers will probably only think of there being two.

The tricky part is that speakers of different accents disagree about which of the two vowel sounds is present at the end of words like taxi. This isn't simple matter of one type of accent being British English, and the other being American English. Pronouncing "ferry" with /ɪ/ is probably very uncommon now in American English, but pronouncing "ferry" with "/iː/" is not uncommon in British English.

It seems like a badly written question. Because length markers are a somewhat common source of confusion, some phoneticians have suggested not using them in transcriptions for foreign learners of English.