What were the causes for the seven years war for British?

In the early 1750s, French expansion into the Ohio River valley repeatedly brought France into armed conflict with the British colonies. In 1756–the first official year of fighting in the Seven Years War–the British suffered a series of defeats against the French and their broad network of Native American alliances.

president thomas jefferson commissioned the expedition shortly after the louisiana purchase in 1803 to explore and to map the newly acquired territory, to find a practical route across the western half of the continent, and to establish an american presence in this territory before britain and other european powers

is it multiple choice