Two statements are provided for evaluation.
Statement-I: Nepal was historically a Hindu Kingdom and subsequently a constitutional monarchy for a considerable period.
This statement is inaccurate. While Nepal was a Hindu Kingdom, its period as a constitutional monarchy concluded in 2008 when the king dissolved the monarchy, leading to Nepal's establishment as a federal democratic republic.
Statement-II: In 2006, pro-democracy movements secured a significant triumph with the king's reinstatement of the House of Representatives.
This statement is accurate. In 2006, a successful pro-democracy movement in Nepal, known as the April Uprising, compelled the restoration of the dissolved House of Representatives, thereby diminishing the monarchy's power.
Consequently, the correct designation is (D) Statement-I is false, while Statement-II is true.