Eyewitness testimony has been found to be most accurate when
a. the witness is presented a simultaneous, as opposed to a sequential, lineup
b. the witness is distracted or must fill in gaps in their memory with stereotyped information
c. the witness has ample time to observe the person under good viewing conditions
d. a weapon is used in the commission of a crime

   C. The witness has ample time to observe the person under good viewing conditions

Explanation:  Of course, testimony is most accurate when the eyewitness has sufficient time to observe the person under good viewing conditions, and can slowly and thoroughly examine anything that would indicate that the person he is observing, i.e. against whom the eyewitness is testifying.

The answer is:

C) the witness has ample time to observe the person under good viewing conditions

Explanation:

It's important to consider that an eyewitness it's not just a person who saw something and can talk about it. The events witnessed has an important role in the record of the events. One way or another, to be a good eyewitness, is necessary that the person must be close (or relatively close) to the object/person it is looking at. Most of it, depending on what is happening with the observed person, the subsequent events would influence the eyewitness. That's why is important to consider the psychological aspects and understand them.  

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