Answer:
A. to join independent clauses that appear to be connected by a conjunctive adverb
Step-by-step explanation:
A semicolon is the symbol ";" and it is used in a variety of situations:
- to separate a series/list that already includes commas
e.g. I travelled to Miami, Florida; Austin, Texas; and Los Angeles, California.
- to join independent clauses that are closely related in thought:
e.g. When I arrived, I thought I would have time to buy a snack; I didn't.
- and many more
However, the main usage of a semicolon is joining independent clauses that "appear to be connected by a conjunctive adverb":
e.g. She didn't study; thus, she failed the test.
The answer is A.