Which broad chronological division is conventionally used to study Vedic society?

Historians commonly distinguish an earlier Rigvedic phase, often placed roughly in the second millennium BCE, from later Vedic developments in the first millennium BCE. Date ranges such as 1500–1000 and 1000–600 BCE are useful conventions, not universally sharp boundaries established by one event. Early or Rigvedic and Later Vedic phases fits that evidence because it matches the specific chronology, agency and function contained in the question. A comparison with the alternatives is useful: Harappan and Mauryan phases, Palaeolithic and Mesolithic phases and Sultanate and Mughal phases are genuine historical terms or names, but each belongs to a different office, patron, text, region or sequence. Reading the question as a relationship among person, period, place and institutional purpose prevents that mistake. The supporting source also helps separate later textbook shorthand from the more precise historical formulation. The compact memory link is therefore Early or Rigvedic and Later Vedic phases together with the factual context above, not the isolated option letter.