What is the topic sentence of paragraph 7 of the passage?
Group of answer choices
“Six years later, he admitted to himself how huge the task was, and he started asking government agencies to launch a clean-up program.”
“Actually, Pregracke first became interested in the riverbanks when he was 17, using a small boat to haul the trash away.”
“That was in 1998, and by 2013, around 70,000 volunteers had removed more than 7.5 million pounds of garbage from along the Mississippi and other rivers in several states.”
“At the age of 23, he formed an organization called Living Lands & Waters, based in East Moline, Illinois, to direct volunteers in clean-up campaigns along a 435-mile stretch of the Mississippi.”
