Explanation:

- In January 2020, a state in India adopted a new logo for its Legislative Assembly.

- The logo features the national emblem and the foxtail orchid, which is the state flower.

- Option 1: Mizoram – Known for its rich cultural heritage but did not adopt a new assembly logo in January 2020.

- Option 2: Meghalaya – A state with vibrant traditions and landscapes; however, it did not change its assembly logo at that time.

- Option 3: Tripura – Known for its diverse communities but not the state in question for adopting the new logo.

- Option 4: Arunachal Pradesh – ? The correct answer. The state's assembly adopted a new logo in January 2020, featuring its state flower, the foxtail orchid, alongside the national emblem.

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