40.

Answer and Explanation

Your Answer is

Correct Answer is F

Explanation

The previous sentence "After his father died, Banneker took charge of the farm and assumed the responsibility of taking care of his mother and younger sister", and the second sentence "he pursued scientific research and taught himself the flute and violin", the preceding and following sentences have no causal relationship and are parallel relation. F is correct.

H/J item: therefore/ in addition is a related adverb and cannot connect two complete sentences.