During the nineteenth century, Britain's urban population increased as its rural population diminished. A historian theorizes that, rather than industrialization's being the cause, this change resulted from a series of migrations to urban areas, each occasioned by a depression in the agrarian economy. To test this hypothesis, the historian will compare economic data with population census data.

The historian's hypothesis would be most strongly supported if which of the following were found to be true？

(A) The periods of greatest growth in the industrial economy were associated with a relatively rapid decline in the rural population.
(B) The periods of greatest weakness in the agrarian economy were associated with relatively slow growth in the population as a whole.
(C) Periods when the agrarian economy was comparatively strong and the industrial economy comparatively weak were associated with a particularly rapid decline in the rural population.
(D) Periods, when the agrarian and industrial economies were both strong, were associated with particularly rapid growth in the urban population.
(E) The periods of greatest strength in the agrarian economy were associated with relatively slow growth in the urban population.