Explanation:
To calculate the minimum baud rate required to sustain a transfer rate of 300 characters per second, we need to consider the number of bits being transmitted for each character, including the data bits, parity bit, and stop bits.

Data Bits:
In this case, we have 8 data bits. Each character is represented by 8 bits.

Parity Bit:
We have a parity bit, which is used for error checking. The parity bit can be set to even or odd parity. Since it is not mentioned in the question, we will assume even parity. The parity bit adds 1 additional bit for each character.

Stop Bits:
We have 2 stop bits. Stop bits are used to indicate the end of a character. Each stop bit adds 1 additional bit for each character.

Total Bits:
So, the total number of bits transmitted for each character is calculated as follows:
8 (data bits) + 1 (parity bit) + 2 (stop bits) = 11 bits

Transfer Rate:
The transfer rate is given as 300 characters per second.

Baud Rate:
The baud rate refers to the number of signal changes per second. In this case, it is equivalent to the number of bits per second since each character is transmitted using 11 bits.

Calculation:
To calculate the minimum baud rate required, we multiply the transfer rate by the number of bits per character:
300 characters per second * 11 bits per character = 3300 bits per second

Therefore, the minimum baud rate required to sustain a transfer rate of 300 characters per second is 3300 baud.

Conversion to Baud Rate:
Baud rates are typically expressed in multiples of 300. To find the closest baud rate, we divide the calculated baud rate by 300 and round it up to the nearest integer:
3300 baud / 300 = 11

The closest baud rate that is greater than or equal to 11 is 12.

Final Answer:
Therefore, the minimum baud rate required to sustain a transfer rate of 300 characters per second is 12 * 300 = 3600 baud. However, since the given options are in bands (bps), we convert the baud rate to the nearest band by multiplying it by 10:
3600 baud * 10 = 36,000 bps

Among the given options, option C (4800 bps) is the closest to the calculated baud rate. Hence, the correct answer is option C.