Answer:
c). because it is being used in place of a person's name.
Step-by-step explanation:
As per the rules of 'Capitalization,' the words used in the position of an individual's name must have their first letter in upper case. Since 'Professor' in the given sentence is employed in the place of the professor's name, its first letter i.e. 'P' would be capitalized. The authority doesn't have a play here as the letter would be capitalized irrespective of what the person is. The word 'Professor' is neither an abbreviation nor it is a general term to refer to someone. It would not be capitalized only when the name is used along with the rank. For example, 'Pardon me, professor Joseph...' Thus, option c is the correct