Timeline cross-check:
India's chronic food-grain shortfall traces back to the Bengal famine of 1943 and the disrupted supply chains of the Second World War, when the country first became critically dependent on imported grain. This dependence intensified through the years immediately surrounding independence in 1947, well before the Green Revolution of the mid-1960s reversed the trend. Since the phrase describes a dependency that had already set in and was widely discussed before the 1950s planning era, it is anchored to the 1940s rather than any later decade.
Hence, the correct answer is the 1940s.