To determine the equation that represents the number of boxes Trina sold, we start by examining the information given:
- Yuri sold 14 boxes.
- Together, they sold a total of 37 boxes.
- Let \( n \) represent the number of boxes that Trina sold.
The equation that represents this scenario can be formulated as:
\[ 14 + n = 37 \]
To isolate \( n \), we can subtract 14 from both sides of the equation:
\[ n = 37 - 14 \]
Calculating this gives:
\[ n = 23 \]
Therefore, Trina sold 23 boxes. The correct equation from the options provided is:
\[ n + 14 = 37 \] and the answer is that Trina sold 23 boxes.