The correct answer is option 4, tobacco. The Vedic people were ancient inhabitants of the Indian subcontinent who lived during the Vedic period, approximately 1500-500 BCE. During this time, agriculture was a major part of their livelihood, and they cultivated various crops such as barley, wheat, and rice. However, tobacco was not known to them during this period. Tobacco is believed to have originated in the Americas and was introduced to the rest of the world after European exploration and colonization. Therefore, it is safe to say that the Vedic people did not have knowledge or cultivation of tobacco as a crop.