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The sense of smell is one of the five senses.
Literal
Sense-of-smell [topic-は] five-senses [possessive-の] one is.
A scientific/educational statement. 嗅覚 (きゅうかく) 'sense of smell'. 五感 (ごかん) 'the five senses' is a set compound for the classical five: 視覚 (sight), 聴覚 (hearing), 嗅覚 (smell), 味覚 (taste), 触覚 (touch). ~の一つ ('one of X') is the standard 'example from a category' phrasing.