The following question contains three statements, one or more of which may not be grammatically correct. You are required to identify the incorrect statements from the options given below and mark that as your answer.
I. The hiking trail offers panoramic views of the rugged mountains, making it a popular destination for avid trekkers.
II. The fashion designer's avant-garde collection challenged traditional norms, pushing boundaries of style and expression.
III. The economic downturn resulted in widespread retrenchments, affecting employees across various industries.