Select the most appropriate 'one word' for the expression given below.
A professional rider in horse race.

Correct option is A

Option a is correct.
A professional rider in horse race- Jockey.
Meanings of other words-
• Horse pilot: The term "horse pilot" is not a commonly used phrase in English and it does not have a standard meaning. It might refer to a person who pilots or guides horses, such as in equestrian sports or in the transportation of horses.
• Autocrat: An autocrat is a ruler who has complete power and authority over a country or group of people
• Cellar: A cellar is a room or space, usually located underground, that is used for storing wine, food, or other provisions.