Why do classification systems change over time?

a. scientists find new evidence in their studies.
b. scientists use old methods of classification.
c. scientists repeat experiments and find no changes.
d. scientists find similar evidence to previous work.

Answer;

A. Scientists find new evidence in their studies.

Explanation;Classification systems are those systems that are used by scientists to classify organisms based on their similarities and differences. These classifications systems may change over as a result of advancement in technology, such as DNA technology which has enabled scientists to find new evidences in their studies and thus re-examine the relationships among organisms.