Explanation:

- Indira Gandhi:

- Indira Gandhi was the Prime Minister of India during the Emergency from 1975 to 1977.

- She declared the Emergency due to internal and external threats to the Indian state.

- This period was marked by significant political unrest and was controversial for the suspension of civil liberties.

- Rajiv Gandhi:

- He was Indira Gandhi's son and also became Prime Minister, but not during the Emergency.

- His tenure as Prime Minister started in 1984 after Indira's assassination.

- Morarji Desai:

- He became Prime Minister in 1977, after the Emergency, leading the first non-Congress government.

- Charan Singh:

- He served as Prime Minister after Morarji Desai, from 1979 to 1980.

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