The correct answer is C. Panel is generally 2D labeled, also size-mutable array.
A Series is a 1D labeled homogeneously-typed array. It is a one-dimensional data structure with a single axis. The data in a Series can be of any type, but all of the values in a Series must be of the same type.
A DataFrame is a general 2D labeled, size-mutable tabular structure with potentially heterogeneously-typed columns. It is a two-dimensional data structure with two axes: rows and columns. The data in a DataFrame can be of any type, and the columns can be of different types.
A Panel is a multidimensional labeled, size-mutable array. It is a three-dimensional data structure with three axes: rows, columns, and panels. The data in a Panel can be of any type, and the columns and panels can be of different types.
Therefore, the statement “Panel is generally 2D labeled, also size-mutable array” is wrong because a Panel is a multidimensional data structure, not a 2D data structure.