The answer is: dubitāre .
<em>Dubitāre </em>in Latin means to doubt, question, hesitate or waver in opinion.
Considering the rest of the alternatives, <em>douten </em>comes from Old French and signifies to dread, fear or be afraid. It is an obsolete word nowadays. As regards <em>douter</em>, it is a French transitive verb that means to hesitate or to doubt.
Answer: Spain should be capitalized and French
Explanation: Countries always gets capitalized.