The correct option is "1 and 3 only" because it accurately reflects the distinctive aspects of Rigvedic Aryan culture compared to that of the Indus Valley Civilization. The Rigvedic Aryans, being a pastoral and warrior society, had technologies such as the coat of mail and the use of horses in warfare, which are well-documented in their texts, whereas the Indus Valley people show no evidence of horse domestication or similar military equipment. Additionally, while both cultures were familiar with metals, the statement regarding the knowledge of gold and silver pertaining to the Rigvedic Aryans is correct; however, the Indus Valley people were also skilled in metallurgy, particularly copper, but there is scant evidence they worked with iron. This nuanced understanding of technological and societal differences is crucial for grasping early Indian history, which is often a focus in UPSC examinations.