Celia is editing the first draft of her research paper about the impact of improper waste disposal on wildlife in Denali Park.

When visitors to the park improperly dispose of their trash, it not only contaminates the environment; it also attracts animals such as grizzly bears to camping sites.

How should Celia correct the underlined part of her sentence?

A.
the environment…it also attracts

B.
the environment, it also attracts
C.
the environment: it also attracts
D.
the environment. It also attracts