​​​​ The exemption under s​ection 54 is allowed only if the capital gain arises from the transfer of a long-term capital asset being a residential house property or land appurtenant thereto whose income is taxable under the head 'Income from house property'.
Here, long-term capital asset means an immovable property (land or building or both), held for more than 24 months immediately preceding the date of transfer.
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