Solution
Option A is the correct answer.
"Gargantuan," means extremely large or enormous.
The opposite of this is "Negligible", meaning something so small or insignificant that it can be ignored.
Option B: Bearable implies something that is tolerable or manageable, which is not opposite to"gargantuan," which is about size or scale.
Option C: Minute means something very small, but this is not the extreme opposite of something enormous like "gargantuan."
Option D: Minimal means the smallest amount, which is not the exact opposite of "gargantuan."