Explanation:

 First option is correct regarding question statement. An ad valorem tax (Latin for "according to value") is a tax whose amount is based on the value of a transaction or of property. It is typically imposed at the time of a transaction.
Clean Energy Cess applied per tonne of coal in India is not ad valorem tax as it is a specific tax. (A per unit tax, or specific tax, is a tax that is defined as a fixed amount for each unit of a good or service sold, such as cents per kilogram. It is thus proportional to the particular quantity of a product sold, regardless of its price.)
'Sales Tax'- A sales tax is a consumption tax imposed by the government on the sale of goods and services.
A value-added tax (VAT) is a type of consumption tax that is placed on a product whenever value is added at a stage of production and at the point of retail sale.
GST is a single tax on the supply of goods and services, right from the manufacturer to the consumer. Credits of input taxes paid at each stage will be available in the subsequent stage of value addition, which makes GST essentially a tax only on value addition at each stage. The final consumer will thus bear only the GST charged by the last dealer in the supply chain, with set-off benefits at all the previous stages.

All of these three are charged as percentage of value or price of the goods and services being bought.