The spelling of the word "Boultel" can be explained using International Phonetic Alphabet (IPA) transcription. The first sound is a voiced bilabial stop /b/, followed by a mid-central vowel /ʌ/. The next two sounds are voiceless alveolar fricatives /s/ and /t͡ʃ/. The final syllable starts with an unstressed schwa sound /ə/, followed by a voiced alveolar lateral approximant /l/. Therefore, the correct spelling of the word "Boultel" is phonemically represented as /bʌlt͡ʃəl/.