What is measured in bits per second, indicating the number of bits that pass through a data line?

The measurement in bits per second that indicates the number of bits that pass through a data line refers to baud rate. Baud rate specifically quantifies the number of signal changes or symbols transmitted per second in a communication channel, which correlates to the transfer of bits if each symbol represents a single bit. In communication theory, baud rate is a critical metric, as it determines the effectiveness and speed of data transmission over networks.

However, it’s also worthwhile to note that while baud rate focuses on signal changes, throughput measures the actual amount of usable data that successfully gets transmitted over the data line in a given time frame, often expressed in bits per second as well. Bandwidth represents the capacity of the communication channel to carry data, while latency is related to the time delay in data transmission. Thus, baud rate specifically addresses the rate of symbol transmission, which is why it is the correct choice in this context.