Option 1 -> lofty means elevated or noble, which is a synonym of sublime, not an antonym.
Option 2 -> exalted means elevated in status or character, which is also a synonym of sublime, not an antonym.
Option 3 -> mundane means ordinary, commonplace, or lacking excitement, which is the opposite of sublime (exceptional/elevated).
Option 4 -> fleeting means brief or short-lived, which refers to duration rather than quality, so it's not an antonym of sublime.
Hence, Option 3: mundane -> "Sublime" describes something exceptional, awe-inspiring, or of elevated quality, while "mundane" describes something ordinary and commonplace, making them perfect antonyms -> correct