In ancient days, a fragile glass jar was considered to be more valuable than a human slave.

Answer: Option C

Fragile : (of an object) easily broken or damaged.
Broad : having a distance larger than usual from side to side; wide.
Tall : of great or more than average height, especially (with reference to an object) relative to width.
Strong : having the power to move heavy weights or perform other physically demanding tasks.
Heavy : of great weight; difficult to lift or move.

Antonym of Fragile is Strong