The correct matching for the following pairs is$$\begin{array}{ll|ll}\hline \text{A.} & \text{All pairs shortest path} & \text{1.} & \text{Greedy} \\\hline \text{B.} & \text{Quick Sort} & \text{2.}& \text{Depth-First Search} \\\hline \text{C.}& \text{Minimum weight spanning tree} & \text{3.} & \text{Dynamic Programming} \\\hline \text{D.} & \text{Connected Components} &\text{4.} & \text{Divide and Conquer} \\\hline \end{array}$$
$\text{A-2 B-4 C-1 D-3}$
$\text{A-3 B-4 C-1 D-2}$
$\text{A-3 B-4 C-2 D-1}$
$\text{A-4 B-1 C-2 D-3}$
Reference: Read the Intro/Algo Sub-Heading.
air1ankit https://www.geeksforgeeks.org/connected-components-in-an-undirected-graph/