Deviation or departure from common rule or standard

Heterogeneity
Anomaly
Unanimity
Anonymity

The correct answer is: B. Anomaly

An anomaly is an occurrence that deviates from what is usual, typical, or expected. It can be a deviation from a standard, rule, or pattern. Anomalies can be caused by a variety of factors, including errors, mistakes, or natural phenomena.

Heterogeneity is the state of being diverse or varied. It can refer to a variety of things, including the diversity of people in a group, the diversity of opinions on a topic, or the diversity of products offered by a company.

Unanimity is the state of being in agreement or consensus. It can refer to the agreement of a group of people on a decision, or the agreement of all parts of a system or structure.

Anonymity is the state of being unknown or unidentified. It can refer to the identity of a person, the identity of a group of people, or the identity of an object.

In the context of the question, the correct answer is anomaly because it is the only option that refers to a deviation from a common rule or standard. The other options do not refer to deviations from common rules or standards.