Answer:
C) speak in front of groups, starting with small groups for short periods, and gradually increase group sizes and speaking duration over time.
Explanation:
In abnormal psychology, phobia is described as an irrational and extreme fear that is being faced by an individual from a particular situation or object. It is often referred to as a kind of "anxiety disorder" because an individual who is experiencing phobia encounters anxiety significantly.
The main symptoms of phobia is environmental factors, family history, distressing situations or events, as well as genetic factors.
As per the question, Alex is dealing with specific phobia of "public speaking".