Chandrakant Parmar 19 September 2021
Dhirajlal Rambhia (SEO Sai Gr. Hosp.) 20 September 2021
It is specified in each sub-section, where the cash payment is disallowed like Sec. 80D for mediclaim as well as for treatment, life insurance premium u/s. 80C, donation u/s 80G, etc. etc. along with limit of any amount that can be allowed for its deduction. So you need to check each and every deduction independently.
CMA Poornima Madhava (CMA) 20 September 2021
No 80d deduction (except for preventive health check up) can be claimed if paid in cash.
Deduction of interest u/s 24(b) is not linked with payment. That is, the deduction can be claimed in the basis of the liability. So may not be a problem I think.
Not sure about 80c.