Final answer:
The 10-letter word for the owner of a hotel is 'hotelier,' which describes a person who owns or manages a hotel.
Step-by-step explanation:
The 10-letter word for the owner of a hotel is hotelier. This term is used specifically to describe someone who owns or manages a hotel. The other options provided do not fit the 10-letter criterion: 'restaurateur' is someone who owns or manages a restaurant, 'concierge' is a hotel employee who provides assistance to guests, and 'innkeeper' refers to one who runs an inn, which is typically smaller than a hotel and may not fit the context of the question. Therefore, the correct choice is b) Hotelier.