B is incorrect.
http://leo.stcloudstate.edu/punct/semicolon.html
and
http://leo.stcloudstate.edu/punct/comma.html
A) On May 30, he suffered a stroke, although he did not realize it, thankfully, he finally saw a doctor on June 2, or else he probably would have had another stroke.
B) On May 30, he suffered a stroke, although he did not realize it; thankfully, he finally saw a doctor on June 2, or else he probably would have had another stroke.
C) On May 30, he suffered a stroke; although he did not realize it; thankfully, he finally saw a doctor on June 2, or else he probably would have had another stroke.
My answer is B
http://leo.stcloudstate.edu/punct/semicolon.html
and
http://leo.stcloudstate.edu/punct/comma.html
I thought that was a comma before "thankfully" in B. I should have my eyes checked.
B is correct.
To determine this, we can analyze each option:
A) This sentence lacks the appropriate punctuation after "it" and "realize it." The comma should be replaced with a semicolon or a period to separate the clauses correctly. Additionally, "thankfully" should be capitalized since it is the start of a new independent clause.
B) This sentence is correctly punctuated, with a comma after "it" and "realize it," and a semicolon after "stroke." The word "thankfully" is capitalized at the start of a new independent clause.
C) This sentence also has incorrect punctuation. The semicolons used to separate the clauses should be replaced with commas to separate the phrases within the clauses correctly.
Therefore, sentence B is the correct choice.