Option 1: Arunachal Pradesh—Sikkim—Mizoram—Himachal Pradesh

This option is incorrect. According to the correct answer, Arunachal Pradesh comes before Mizoram in terms of population density.

Option 2: Arunachal Pradesh—Mizoram—Sikkim—Himachal Pradesh

This option is correct. According to the Census 2011, Mizoram has the highest population density among these four states, followed by Arunachal Pradesh, Sikkim, and Himachal Pradesh. Therefore, this option represents the correct ascending sequence of states based on their population density.

Option 3: Mizoram—Arunachal Pradesh—Himachal Pradesh—Sikkim

This option is incorrect. According to the correct answer, Sikkim comes after Himachal Pradesh in terms of population density.

Option 4: Arunachal Pradesh—Himachal Pradesh—Sikkim—Mizoram

This option is incorrect. According to the Census 2011, Mizoram has the highest population density among these four states, so it should come after Sikkim in the ascending sequence.

In conclusion, the correct ascending sequence of states based on