Statement : There are no river sand quarries employing machines and sand extraction is done manually and transportation through carts.
I. The river sand quarries used to deploy machinery for sand extraction and for transportations.
II. The sand quarrying industry is hit because of the government directive to stop using machinery for sand extraction and transportation
We can’t infer from assumption I if sand quarries used to deploy machinery earlier and we also don’t know if there was any government directive as stated in assumption II. Hence correct answer option is 4.