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.
Ecosystem is that it is a community or group of living organisms that live in and interact with each other in a specific environment.
For instance, tropical forests are ecosystems made up of living beings such as trees, plants, animals, insects and micro-organisms that are in constant interaction between themselves and that are affected by other physical (sun, temperature) or chemical (oxygen or nutrients) components.
An ecosystem consists of a community of organisms together with their physical environment.
Ecosystems can be of different sizes and can be marine, aquatic, or terrestrial. Broad categories of terrestrial ecosystems are called biomes.
In ecosystems, both matter and energy are conserved. Energy flows through the system—usually from light to heat—while matter is recycled.
Ecosystems with higher biodiversity tend to be more stable with greater resistance and resilience in the face of disturbances, or disruptive events.
Mass is the amount of matter in any object.
Answer: the proper number of chromosomes.
Explanation:
D. Density increases is the correct answer!