Which of the following relation is valid?
Where MTBF = Mean Time Between Failures
MITTF = Mean Time To Failures
MTTR = Mean Time To Repair

A

$$MTBF = MTTF + MTTR$$

B

$$MTTR + MITF + MTBF = 1$$

C

$$\frac{1}{MTTR} + \frac{1}{MTTF} + \frac{1}{MTBF}$$

D

$$MTBF . MITF . MTTR = 1$$