The number of product terms in the minimized sum-of-product expression obtained through the following $\text{K}$-map is (where, " $d$ " denotes don't care states)
$$\begin{array}{|c|c|c|c|} \hline 1 & 0 & 0 & 1 \\ \hline 0 & d & 0 & 0 \\ \hline 0 & 0 & d & 1 \\ \hline 1 & 0 & 0 & 1 \\ \hline \end{array}$$
- $2$
- $3$
- $4$
- $5$