In the node analysis method, what is the recommended characteristic of a reference node?

Correct option is A

​$$\text{In node (nodal) analysis, a reference node is chosen to simplify calculations:} \\[8pt]\bullet \ \text{It is assigned zero voltage (ground).} \\[4pt]\bullet \ \text{All other node voltages are measured with respect to this node.} \\[4pt]\bullet \ \text{Choosing ground as the reference reduces the number of unknown node voltages and simplifies equations.}$$​​