Answer:
D. A person who claimed to see a car of a certain make/model leaving the scene of a crime
Step-by-step explanation:
It is D because it would be the closest possible lead for finding who did the crime. Anyone around the time of the murder and anyone going in and out at the time is a suspect, even the eyewitness. If the eyewitness saw someone leaving the location moments before it was reported, that would be suspicious.
(lol among us vibes. it hyped me up for this moment.)
The medical examiner who found poison in the victim's stomach
It would not be this one because they were called after the crime took place, the medical examiner only saw the aftermath of said way to k!ll the person.
An expert discussing evidence collected during an investigation
The expert collected data of the crime scene after it had happened. Otherwise, this would not have been possible. So, they were not an eyewitness since they were not present at the time.
A defendant's best friend, who was out of town when the crime was committed
How would the addressed person out of town see the crime scene? Maybe they were threatened to leave the city? Anyway, it just would not make since for the best friend to be an eyewitness at the time of the crime if they were miles away.