Correct Answer & Explanation
Option A
• 'Obdurate' means stubbornly refusing to change one's opinion or chosen course of action.
• 'Adamant' is a precise synonym meaning unyielding, inflexible, and determined.
• Other options: 'Delicate' means easily damaged/brittle, 'Charitable' means generous/benevolent, and 'Dreary' means bleak/dismal.