Final answer:
The word derived from the Old English 'seofon' is 'Seven', and it has a short sound. Understanding the vowel sounds and spelling patterns is crucial in English studies.
Step-by-step explanation:
The 5-letter word that comes from the Old English "seofon" is B) Seven. In English language studies, understanding word origins is essential. The word 'seven' has a short sound, similar to words like 'slept' and 'dense' which also have a short , contrasted with words like 'green' and 'beam' that contain a long . When learning about English vocabulary and spelling, recognizing the vowel sounds and spelling patterns helps in identifying how words are constructed and pronounced.