Selecting Text
Click on the Select text icon 
on the toolbar, then drag the mouse to select the desired objects. When right-clicking on the mouse (Mac: Ctrl + Click), a menu will appear giving you the choice to copy the text to the clipboard; highlight, underline, cross out, squiggly underline, or replace the selected text; or insert new text after the selection.
Note : When copying text PDF Studio will preserve Font, Color, Size, Bold & Italic properties of the selected text.
To exit the selection mode, simply click on the hand tool 
or Esc on the keyboard.
Rectangular Text Selection
For rectangular text selection, hold down Ctrl (⌘ for macOS) while dragging the mouse. The cursor will change to 
to indicate that a different selection mode is active.
Text Selection Options
Copy to Clipboard - copies the selected text to the OS clipboard
Copy Text as Table - copies the selected text to the OS clipboard as a CSV comma delimited table
Paste - pastes the content currently stored in the OS clipboard into the document
- Text: will be pasted as a Text Box Comment
- Image: will be pasted as an image stamp
- File Data: will be pasted as an attachment
Extract - extract plain text or text as a table (CSV)
- Extract Text - selected text is extracted as plain text file .txt
- Extract Text as Table (CSV) - selected text is extracted as comma delimited CSV file
Markup Tools
Highlight Text - highlights the selected text
Underline Text - underlines the selected text
Cross Out Text - adds cross out to selected text
Replace Text - adds replace text markup to selected text
Mark for Redaction - add redaction annotation to selected text
Other
Create Link - creates an interactive link on the selected text
Create Bookmark - creates a bookmark at the current position using the selected text
Search
Search Google for... - performs a Google search with the selected text