Answer:
C. the behavior of an organism in a particular situation
Two or more organs form together make organ systems.
<u>Explanation:</u>
The basic unit of living organisms is the cell. Multiple cells makes up tissues and tissues make up organs. Two or more organs make up the organ system.
Human body has several organ systems. The organs that make up an organ system can be internal as well as external. Respiratory system is made up of organs like lungs, nose, pharynx, trachea, diaphragm etc. digestive system is made with organs like liver, small intestine, stomach, mouth , large intestine, pancreas etc.
Corpus Callosum is a band of thick fibres which connects the hemispheres of the brain.
Answer= Because polar bears depend on ice as a habitat to survive the more the temperature is rising and the sea ice melting as a result of global warming there is basically a possibility that the population of polar bears will decline because there will be no home (habitat)left for them to breed(survive)in.