To answer this question, we need to understand the context of the story. In the Hindu epic, Ramayana, King Janaka organized a swayamvara (a ceremony where a princess chooses her husband) for his daughter, Sita. As part of the swayamvara, King Janaka set a challenge for suitors to demonstrate their strength and ability by attempting to string a divine bow.
The correct answer is D) Shiva's. King Janaka made each of Sita's suitors try to string the bow belonging to Lord Shiva. This bow was incredibly heavy and powerful, and only someone of great strength and divine nature could successfully string it.