Hello!
I believe the correct answer to your question would be sister chromatids.
Hope this helps, and have a lovely rest of your day :)
The basic repeating unit of nucleic acids are known as nucleotides
An example of something that does not have mass would most likely be air. Because in order for something to have mass, it must take up space and have shape. Anything that you can think of that does <u>not</u> have <u>space or shape</u> does not have mass.
The answer is C, a hererotroph !
