Einstein and Hawking are famous people who relied upon thought without words.
Thought without words (B) would be reflected by a child who pulled a chair over to assist with an intended ascent to a forbidden cupboard.
Verbal Thought (C) is forged when speech becomes internalized. It interfaces with the thought processes to create a new kind of thinking--verbal thought which is called language. We still retain, however the ability for speech without thought, for example, “Hey diddle diddle, the cat and the fiddle the cow jumped over the moon…”
On the other hand some of our greatest thinkers, such as Einstein and Hawking, describe how they visualized the structure of the universe in non verbal models and then only after that described them with numbers and words.
So how and when does this merger of thought and speech occur?