Consider a sequence of vectors represented as $\mathbf{k}_1, \mathbf{k}_2, \dots, \mathbf{k}_{10}$. Which of the following options correctly identifies the subset of vectors described by the notation ${\mathbf{k}_{i-n_c+1}, \dots, \mathbf{k}_i}$ when the current position i is 7 and the context window size n_c is 4?

In sequence modeling, the notation ${\mathbf{k}_{s}, \dots, \mathbf{k}_i}$ is used to represent a context window of size $n_c$ ending at index $i$. To correctly define this window, the starting index, $s$, must be equal to the expression ____.

Applying Context Window Notation