Match the following:
$$\begin{array}{|l|l|l|l|} \hline a. & \text{Canonical Parser} & 1. & \text{No adjacent nonterminals} \\ \hline b. & \text{SLR(1) Parser} & 2. & \text{Follow sets must be disjoint} \\ \hline c. & \text{LL(1) Parser} & 3. & \text{Most powerful parser} \\ \hline d. & \text{Operator Precedence Grammar} & 4. & \text{Top-down parser} \\ \hline \end{array}$$
- $a-2; b-3; c-1; d-4$
- $a-3; b-4; c-2; d-1$
- $a-2; b-1; c-4; d-3$
- $a-3; b-2; c-4; d-1$