Explain why the presence of "ghost nets" in the ocean is an important problem to solve

Ghosts net are abandoned fishing gear which is increasingly made of the durable material that lasts for a long time. These nets float and drift through the oceans and damage the marine life. Many sea species are caught in them and can not get out. These "ghost nets" are also damaging to coral reefs and many of them do look like they have run over by  a truck because of this fishing gear. That is why this problem needs to be solved.

The answer would be b.