Explanations:The term "Rajputana" was used by the British to refer to the region that is now Rajasthan during the 19th century. This name was adopted to describe the area under the influence of various Rajput kingdoms. The term "Rajputana" is derived from the words "Rajput" and "Ana," meaning "land of the Rajputs." The Rajputs were a group of warrior clans who ruled various kingdoms in the region.
The British East India Company began to exert influence over the Indian subcontinent in the late 18th century, and by the early 19th century, they had established a significant presence in the region. The British used the term "Rajputana" to describe the area that was under the control of various Rajput states. This term was used to distinguish the region from other parts of India that were under direct British rule or control.
The use of the term "Rajputana" by the British reflects the period of significant British influence in India, which began in the 19th century. The British adopted this term to describe the region during this period, and it remained in use until the independence of India in 1947. After independence, the region was renamed "Rajasthan," which means "land of the kings," reflecting the historical significance of the Rajput kingdoms in the region.
It is important to note that the term "Rajputana" was not used by the British in earlier centuries, such as the 12th, 17th, or 18th centuries. The British influence and the use of the term came much later, in the 19th century. Therefore, the correct answer is the 19th century, as this is the period when the British used the term "Rajputana" to describe the region that is now Rajasthan.