Final answer:
The correct verb to fill in the blank is 'hable.'
Step-by-step explanation:
The correct verb to fill in the blank in the sentence is hable.
The sentence is in the subjunctive mood, which is used to express doubt, uncertainty, desire, or a contrary-to-fact condition. In this case, it is expressing doubt or disagreement with the statement 'Tomás speaks French.'
Therefore, the correct verb form is the third person singular form of hablar, which is hable.
Learn more about Using the subjunctive mood in Spanish