Assertion: Recent archaeological finds suggest that copper was also probably brought from Oman by the people of the Harappan civilisation.
Reason: Chemical analyses have shown that both the Omani copper and Harappan copper artefacts have traces of nickel, suggesting a common origin.

Both the Assertion and the Reason are correct and the Reason is the correct explanation of the Assertion.

The correct answer is Option 1 - Both the Assertion and the Reason are correct and the Reason is the correct explanation of the Assertion.

Recent archaeological finds suggest that copper was also probably brought from Oman (Assertion), on the southeastern tip of the Arabian peninsula. Chemical analyses have shown that both the Omani copper and Harappan artefacts have traces of nickel, suggesting a common origin (Reason). There are other traces of contact as well. A distinctive type of vessel, a large Harappan jar coated with a thick layer of black clay has been found at Omani sites. Such thick coatings prevent the percolation of liquids. We do not know what was carried in these vessels, but it is possible that the Harappans exchanged the contents of these vessels for Omani copper.