Answer:
The correct option is A. A directory of relatives' phone numbers
Explanation:
Family communication plan is a measure taken to contact the relatives of a person if an emergency situation arises for a person. In today's modern world, emergencies can happen at any time so it is very important to have a family communication plan so that the relatives of a person be informed immediately. Hence, option A is correct.
Other options are false because none of the other options will be usable in case of an emergency.
A) a common ancestor
Homologous structures are structures that are similar in related organisms. There is a basic pattern of bones which can be inherited from a common ancestor
Determination of specific cells for certain functions changes resulting from induction the occurrence of mRNAs for the production of tissue-specific proteins changes in the size and shape of the cell cell.
The number of oxygen atoms in a molecule
Overlapping niches lead to competition because they need the same resources such as food sources
