The problem of dowry in our country has assumed gargantuan proportions

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."