ROE Engineering, A Chinese shipbuilding company, agrees to build a fleet of submarines for the Sri Lankan Navy, for which it will be paid in Sri Lankan currency. As per the agreement, ROC must also spend a substantial amount of the money it generates through this deal within the country. In accordance with the contract, ROC bus Sri Lankan tea at a reduced rate, This is an example of which of the following forms of countertrade?

1) offset

2) descending bid

3) barter

4) compensate deal