In which case, a registered dealer has to issue a payment voucher?

The answer is: A. Reverse Charge.

A registered dealer has to issue a payment voucher in case of a reverse charge. A reverse charge is a mechanism in which the recipient of goods or services is liable to pay the tax instead of the supplier. This is done to ensure that tax is paid on all transactions, even if the supplier is not registered for GST.

A casual taxable

person is a person who undertakes a taxable activity occasionally or for a short duration. They are not required to register for GST unless their aggregate turnover in a financial year exceeds Rs. 20 lakh.

An export is a supply of goods or services to a place outside India. Exports are not subject to GST.

A composition dealer is a dealer who has opted to pay a

fixed percentage of their turnover as GST instead of paying GST on all their supplies. Composition dealers are not required to issue payment vouchers.