What was the main reason for the remarkable growth in population during the first half of the eighteenth century?

The main reason behind the exponential growth of population during the first half of the 18th century was the overall improvement of living conditions in households throughout western Europe.

Hygienic conditions vastly improved, as well as the introduction of medical developments, such as the discovery of the smallpox vaccine, which contributed to a fall in mortality rates due to this reason.

i think the answer is b.

i believe the answer is d.