Final answer:
Aircraft carriers were not a new weapon used in WW1. Other new weapons used during the war included airplanes, poison gas, and submarines.
Step-by-step explanation:
The correct option is c. aircraft carriers. Aircraft carriers were not used as a new weapon in WW1. They were first introduced and used extensively in naval warfare during World War II. During World War I, however, a variety of new weapons were introduced, such as airplanes, poison gas, and submarines.
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