The correct answer is: C. 28000 bits/sec
The maximum information rate for a Gaussian channel is given by the Shannon-Hartley theorem:
$$C = B \log_2(1 + \frac{S}{N})$$
where $C$ is the maximum information rate in bits per second, $B$ is the bandwidth in hertz, $S$ is the signal power in watts, and $N$ is the noise power in watts.
In this case, we are given that $B = 1$ MHz and $S/N = 104$. Substituting these values into the Shannon-Hartley theorem, we get:
$$C = 10^6 \log_2(1 + \frac{10^4}{1}) = 28000\text{ bits/sec}$$
Therefore, the maximum information rate for this Gaussian channel is 28000 bits per second.
Option A is incorrect because it is the signal power in watts, not the maximum information rate.
Option B is incorrect because it is the noise power in watts, not the maximum information rate.
Option D is incorrect because it is the bandwidth in hertz, not the maximum information rate.