Rate of tax for service income (along with trading income) of a composite dealer

Facts: 1. A retail trader opted for composition. 2. During the year 2019-20 he made a turnover of 45 Lakhs and Facts: 1. A retail trader opted for composition. 2. During the year 2019-20 he made a turnover of 45 Lakhs and paid 1% Gst. 3. At the time of filing income tax return auditor observed service income (commercial rents) of Rs. 1.50 Lakhs in books. (Less than 10% of turnover). Question : At what rate GST on service income is to be discharged? Options: a) 1% b) 6% c) Dealer shall not have opted for composition in this case as service income exists. Please advise. 10% of turnover). Question : At what rate GST on service income is to be discharged? Options:
a) 1% b) 6% c) Dealer shall not have opted for composition in this case as service income exists.

Please advise.