Answer:
The population first grows, stabilizes, and then declines.
Explanation:
A researcher is studying a population with a unique age structure. An age structured histogram he has developed over the course of several decades has undergone transformations in shape, from a pyramid shape to a roughly rectangular shape to an inverted pyramid shape (where the base is narrower than the top). The population first grows, stabilizes, and then declines.
TRNA reads codons from mRNA and then brings attached amino acids accordingly. Amino acids are connected in long chains called proteins.
That answer would be A. nucleus