The following excerpt is from a book of the discovery of Neanderthal skull in beligum:

"As Dr. fuhlrott has not yet published his description of these circumstances, I borrow the following account on them for one of his letters. 'A small cave or grotto high enough to admit a man, and about 15 feet deep from the entrance. . .exists in the southern wall of the gorge of the Neanderthal . . .about 60 feet above the bottom of the valley.

Which of the following best describes the account from the letter excerpt ?

A. it is primary source because it was written by someone who was present at the discovery of the skull
B. it is a secondary source because it was written after the discovery of the skull was made

C. it is a primary source because it provides an accurate description of the caves where the skull was made

D. it is a secondary source because it appears in a text book printed years after discovery