The answer is MEASURE.
<span>Psychologists need to decide how they will MEASURE the phenomenon they are interested in so that they can describe that phenomenon.
Psychologists scientific method to collect data that they need to measure. They use this method because it is the most accurate and most commonly used technique in data collection. </span>
I would go with D, speaker. A poem is written by an author, but the author isn't always the speaker.
The answer is: Abscisic acid.
