A Point Which Is Outside of the Lower Control Limit

Multiple Choice

A point which is outside of the lower control limit on an R-chart:

A) is an indication that no process variation is present.
B) should be ignored because it signifies very low process variation.
C) should be investigated because it could indicate improvements in the methods used in a process.
D) should be ignored unless another point is outside that limit.
E) is impossible because the lower limit is always zero.