Explanation:

- Option 1: Dalai Lama - The Dalai Lama is the spiritual leader of Tibetan Buddhism. While he is highly revered, the Hemis Tsechu festival is not dedicated to his birth anniversary.

- Option 2: Gautama Buddha - He is the founder of Buddhism. Many festivals celebrate his life and teachings, but Hemis Tsechu is not specifically for him.

- Option 3: Guru Padmasambhava - The Hemis Tsechu festival indeed commemorates the birth anniversary of Guru Padmasambhava, an important figure in Tibetan Buddhism known for spreading Buddhism in Tibet.

- Option 4: Adi Shankaracharya - He was a philosopher who consolidated the doctrine of Advaita Vedanta, but he is not related to the Hemis Tsechu festival.

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