i would say D. ! :) let me know if this is correct
A first-hand source such as an experiment is called a primary source.
A primary source is where you can share new information or report on what you have discovered. Some primary sources are research data, interviews, audio recordings, and autobiographies.
A secondary source is where you describe and discuss about the primary sources. They are used to collect and gather primary source information. Some secondary sources are textbooks, review articles, and scholarly books.
A tertiary source is a source about summaries. A tertiary source can be used to look up information or get an overview about what it is you are wanting to know. Some tertiary sources are dictionaries, handbooks, encyclopedias, Wikipedia, and guidebooks.
The right answer is A mutation.
Alteration of the genetic material (DNA or RNA) of a cell or virus that causes a change in certain traits due to the inheritance of this genetic material from generation to generation.
Abnormal modification of the DNA of a gene, either spontaneously during cell division, or under the influence of external agents called mutagens. This gene is modified to be transmitted to the daughter cells. Some mutations have no effect on the cell. Others are the first step in a long process of cancerization.
Rare are the mutations that are beneficial.