how would I go about figuring this out what are we looking for when we ask best model is it supposed to be closer to 1 or 0 ?

Accuracy Table: \begin{tabular}{|l|l|l|} \hline Max Depth & Train set Accuracy & Validation set Accuracy \\ \hline 1 & 0.7877 & 0.7857 \\ \hline 2 & 0.7923 & 0.7476 \\ \hline 3 & 0.8523 & 0.819 \\ \hline 4 & 0.8754 & 0.8238 \\ \hline 5 & 0.8908 & 0.8333 \\ \hline 6 & 0.9200 & 0.8476 \\ \hline 8 & 0.9554 & 0.8476 \\ \hline 10 & 0.9862 & 0.8000 \\ \hline 13 & 1.0000 & 0.8000 \\ \hline \end{tabular} ii. Which model(s) underfit the data? iii. Which of these is the best model