The year 1917 was important for the wright brothers because
a) their first successful flight occurred.
b) their patent expired.
c) they began to work for the army.
d) they began to work for the british air force.

The correct answer is B. Their patent expired.

The year of 1917 was important for the wright brothers because their patent got expired.

Wright brothers were Wilbur and Orville. They were aviation pioneer, engineers, inventors, and American aviators. During their first practical is when they fixed a wing in an aircraft.

In the year 1903 is when they made an heavier craft than air. The two brothers had a breakthrough which was fundamental when they had an invention of three axis control.

This allowed the pilot to maintain equilibrium and also to steer effective the aircraft..

B) their patent expired.

Explanation:

answer: the correct answer is c.

explanation:

all of the