Question

Which of the following best describes how aircraft changed during the course of World War I?
Aircraft became heavier and were used for bombing the enemy.
Aircraft became faster and were used to carry heavier loads.
Aircraft became slower and were used for reconnaissance.
Aircraft became slower and were used for bombing the enemy.

Answer 1

"Aircraft became faster and were used to carry heavier loads."

Early in WWI planes were mainly slow recon machines; during the war engines, structures and aerodynamics improved, producing faster aircraft capable of carrying more weapons and bombs.