In a DOCSIS network, why is the data throughput over the return or upstream path typically less than the throughput of data over the forward or downstream path?
a) The return path has wider bandwidths and higher transmit power compared to the downstream path.
b) The upstream path experiences less congestion compared to the downstream path.
c) The data throughput is equal in both the upstream and downstream paths.
d) Compared to the downstream path, the narrower bandwidths and lower transmit power of the modems used to transmit data over the return path cause the downstream and upstream data throughput to be unequal or asymmetrical.