The four sentences (labelled $\text{A, B, C, D})$ below, when properly sequenced would yield a coherent paragraph. Decide on the proper sequencing of the order of the sentences and key in the sequence of the four numbers as your answer:
- Tensions and sometimes conflict remain an issue in and between the $11$ states in South East Asia (Brunei Darussalam, Cambodia, Indonesia, Laos, Malaysia, Myanmar, the Philippines, Singapore, Thailand, Timor$-$Leste and Vietnam).
- China’s rise as a regional military power and its claims in the South China Sea have become an increasingly pressing security concern for many South East Asian states.
- Since the $1990$s, the security environment of South East Asia has seen both continuity and profound changes.
- These concerns cause states from outside the region to take an active interest in South East Asian security.