Answer: Gaining or losing a chromosome will result in major genetic changes for that horse, as either it will be missing important DNA or will have too much DNA. Either can cause mutations to occur in the animal's genome. Chromosomal changes are caused by an error during either meiotic or mitotic cell division. An error could be that a cell has too much copies of a chromosome, or not enough, which causes the mutations mentioned above. Hope this helps some, I know it's not a super meaty answer.
Explanation: It is A because the television gives off light and sometimes that could heat up the tv and it is sound because obviously television makes sounds because of the volume :) hopefully that helps.