can + have / has?

A large company can ____ more flexibility in its employment policies than a small firm.

‘have’ or ‘has’ which one would fit the sentence? and why?

have

Modal verbs are special verbs which behave very differently from normal verbs. Here are some important differences:
1. Modal verbs do not take “-s” in the third person.

Examples:

He can [color=red]speak Chinese.

Common Modal Verbs
Can
Could
May
Might
Must
Ought to
Shall
Should
Will
Would

Thank you again Ms.Milanya.
You always here on the forum, and you’ve answered many questions from me.
Thanks a lot for helping me improve english.