Final answer:
The Guru Granth Sahib includes the compositions of c. six Gurus: the first five Sikh Gurus and the ninth Guru, Guru Tegh Bahadur, making option C the correct answer.
Step-by-step explanation:
The Guru Granth Sahib contains the compositions of c. six Gurus. The correct answer to the question regarding the number of Gurus whose compositions are included in the Guru Granth Sahib is option C) Six Gurus: First Five Gurus & the Ninth Guru.
This means that the sacred scripture contains the teachings of Guru Nanak Dev Ji, who was the founder of Sikhism and the first of the Sikh Gurus, as well as those from the second, third, fourth, and fifth Gurus, and the compositions of the ninth Guru, Guru Tegh Bahadur.