The correct answer is C. Bit error rate.
A bit error rate (BER) is a measure of the number of bit errors that occur per unit time or per unit distance in a digital communication system. It is usually expressed as a percentage or as a ratio of the number of bits in error to the total number of bits transmitted.
A bit error can occur due to a number of factors, such as noise, interference, or hardware failure. The BER is an important parameter in the design and performance evaluation of digital communication systems.
A. Equally likely event is an event that has an equal probability of occurring. For example, the probability of rolling a 6 on a six-sided die is 1/6.
B. Exhaustive events are events that cannot occur at the same time. For example, the events “the coin lands heads” and “the coin lands tails” are exhaustive events.
D. Outage event is an event in which a communication system is unable to provide the required service. For example, an outage event might occur due to a power outage or a hardware failure.