Which of these endings will not create parallel structure for the following sentence stem?

He was tall, quiet, and

If you want to create a parallel structure, you need to use the same form of the word throughout the sentence. So here, there are two adjectives, tall and quiet, meaning that the third word also has to be an adjective. Very mysterious, somewhat handsome, and well dressed are all adjectives, but will wear all black is not, which is why that is the correct answer.