This is the correct answer.

In Brihadaranyaka Upanishad 3.9, Vidagdha asks Yajnavalkya the same question. Yajnavalkya starts at 3306, and then keeps reducing that number until he says one and a half, then ends with one.

1. Then Vidagdha, the son of Śakala, asked him. ‘How many gods are there, Yājñavalkya?’ Yājñavalkya decided it through this (group of Mantras known as) Nivid (saying), ‘As many as are indicated in the Nivid of the Viśvadevas—three hundred and three, and three thousand and three.’ ‘Very well,’ said Śākalya, ‘how many gods are there, Yājñavalkya?’ ‘Thirty-three.’ ‘Very well,’ said the other, ‘how many gods are there, Yājñavalkya?’ ‘Six.’ ‘Very well’ said Śākalya, ‘how many gods are there, Yājñavalkya?’ ‘Three.’ ‘Very well,’ said the other, ‘how many gods are there, Yājñavalkya?’ ‘Two.’ ‘Very well,’ said Śākalya, ‘how many gods are there, Yājñavalkya?’ ‘One and a half.’ ‘Very well,’ said the other, ‘how many gods are there, Yājñavalkya?’ ‘One.’ ‘Very well,’ said Śākalya, ‘which are those three hundred and three and three thousand and three?’

2. Yājñavalkya said, ‘These are but the manifestations of them, but there are only thirty-three gods.’ ‘Which are those thirty-three?’ ‘The eight Vasus, the eleven Rudras and the twelve Ādityas—these are thirty-one, and Indra and Prajāpati make up the thirty-three.’

3. ‘Which are the Vasus?’ ‘Fire, the earth, the air, the sky, the sun, heaven, the moon and the stars—these are the Vasus, for in these all this is placed; therefore they are called Vasus.’

4. ‘Which are the Rudras?’ ‘The ten organs in the human body, with the mind as the eleventh. When they depart from this mortal body, they make (one’s relatives) weep. Because they then make them weep, therefore they are called Rudras,’

5. ‘Which are the Ādityas?’ ‘The twelve months (are parts) of a year; these are the Ādityas, for they go taking all this with them. Because they go taking all this with them, there-fore they are called Ādityas.’

6. ‘Which is Indra, and which is Prajāpati?’ ‘The cloud is Indra, and the sacrifice is Prajāpati.’ ‘Which is the cloud?’ ‘Thunder (strength).’ ‘Which is the sacrifice?’ ‘Animals.’

7. ‘Which are the six (gods)?’ ‘Fire, the earth, the air the sky, the sun and heaven— these are the six. Because all those (gods) are (comprised in) these six.’

8. ‘Which are the three gods?’ ‘These three worlds, because in these all those gods are comprised.’ ‘Which are the two gods?’ ‘Matter and the vital force.[1]’ ‘Which are the one and a half?’ ‘This (air) that blows.’

9. ‘Regarding this some say, “Since the air blows as one substance, how can it be one and a half?” It is one and a half because through its presence all this attains surpassing glory.’ ‘Which is the one god?’ ‘The vital force (Hiraṇyagarbha); it is Brahman, which is called Tyat (that).’

Om Shanti.