Mill's method of concomitant variations helps to identify causes by observing:

A) whether adding additional factors results in an increase or decrease in the effect
B) whether an increase or decrease in the suspected cause results in an increase or decrease in the effect
C) a larger sample of instances
D) a more diverse sample of instances
E) whether the effect varies over time, while the suspected causal factor remains the same

Mill's method of concomitant variations involves observing whether an increase or decrease in the suspected cause results in an increase or decrease in the effect. This helps to identify a causal relationship between the two variables. Option A is close, but it is not about the suspected cause but additional factors. Option C and D are not related to Mill's method of concomitant variations. Option E is also not related as it suggests a variation in effect over time, which is not necessarily related to the suspected cause.