Question

the tiktaalik fossil, which dates back 375 million years, is considered a transitional fossil because
the species lived while earth was still forming.
it shows the transition between two- and four-legged organisms.
it was discovered half in the water and half on land.
it displays features found on both aquatic and land - dwelling species.
the organism was swimming when it was crushed by falling rock.

Explanation:

A transitional fossil is one that shows characteristics of two different groups of organisms. The Tiktaalik fossil has features of both aquatic (like fish - e.g., fins) and land - dwelling (like tetrapods - e.g., wrist - like structures) species. Earth was not still forming 375 million years ago. It is not about the number of legs (two - legged organisms are not a major group in this context). Where it was discovered (half - in - water and half - on - land) is not the defining characteristic of a transitional fossil. How it died (swimming when crushed) is also not relevant to it being a transitional fossil.

Answer:

it displays features found on both aquatic and land - dwelling species.