What is the simplified form of 4 log₃y - 6 log₃x - 7 log₃z?
a. log₃ ((xz)¹⁰/(y)⁷)
b. log₃(y⁴z⁷/x⁶)
c. log₂(24xy/7z)
d. log₂(5yz/x)