Which of these represents the most significant reason why historians and archaeologists know relatively little about the Indus River Valley civilization?
A) their writing has not yet been deciphered
B) people have not considered it a valid subject to study
C) modern governments refuse to allow experts into the area
D) there is not proof that the civilization actually existed
If this is your question, then the answer is
A) their writing has not yet been deciphered
Hope This Helps, Good Luck!