Answer:
he was among the first propose its existance
The answer is "On several occasions" because it gives an example of its hunting skills afterwards
Some are rumours or false stories
Adolf Hitler was the Nazis leader since 1921
The correct answer is social loafing.
Social loafing refers to the phenomenon where a person puts in less effort to achieve a goal, when he/she is part of a group, compared to when he/she is working alone. Social loafing usually occurs due to diffusion of responsibility, where a person feels less responsible and motivated to help out, when he/she is in a group with other people. In this instance, Carlene demonstrates that she dislikes social loafing because she believes that when working in a group, there is always going to be someone who is content to sit back and let others do the work.