org-latex-listings-options

org-latex-listings-options is a variable defined in `ox-latex.el'.
Its value is

nil

Documentation:
Association list of options for the latex listings package.

These options are supplied as a comma-separated list to the
\lstset command. Each element of the association list should be
a list containing two strings: the name of the option, and the
value. For example,

(setq org-latex-listings-options
'(("basicstyle" "\\small")
("keywordstyle" "\\color{black}\\bfseries\\underbar")))

will typeset the code in a small size font with underlined, bold
black keywords.

Note that the same options will be applied to blocks of all
languages.

You can customize this variable.