Copying text is a basic part of working with computers. Why does BC copy an entire row with the command-C keyboard command? It's ridiculous and not helpful. Why can't you use the shift key to select from the cursor's current position to another position in the string? Again, NOT HELPFUL. What could the rationale possibly be for making these ubiquitous functionalities not work in BC?
And no, you do not have to have the entire row selected to copy the entire row. The entire row is copied even when only specific text is selected.