Answer:
Diagnostic trait
Explanation:
The morphological species concept is the concept that defines a species terms of their morphological traits.
The morphological species concept is used to define the species which cannot reproduce sexually so it is applicable to the asexual organism like bacteria and used to describe the fossil species.
The morphological concept defines a species as a community of organism which has similar morphological traits called Diagnostic traits which help the biologist to recognize the species.
Thus, the Diagnostic trait is the correct answer.
