Assertion: Living systems are closed systems.
Reason: Energy of living organisms cannot be lost or gained from environment.
A. Both Assertion and Reason are true and Reason is the correct explanation of Assertion.
B. The Assertion and Reason are true but Reason is not correct explanation of Assertion.
C. Assertion is true but, Reason is false
D. Assertion is false but, Reason is true.

Hint: Living system is self-organizing life forms that interact with the environment.
These systems are maintained by the flow of:
1. Information
2. Energy
3. Matter
In the last few decades, some scientists proposed the general living systems that are required to explain the nature of life.

Step by step answer:Living system is a biological system which is an open type of system. It is self-organizing life forms in which organisms interact with the environment. It arises from the ecological and biological sciences. Living systems can be as simple consisting of a single-cell or can be complex as a supranational organization such as the European Union. Regardless of their complexity, they all depend upon the same important twenty subsystems in order to survive and to continue the propagation of their species or types beyond a single generation. So, it is very important to know how the solar energy captured by the plants flow through different organisms of an ecosystem. All organisms depend upon the producers for their food either directly or indirectly. Therefore, there is a unidirectional flow of energy from the sun to producers and then to the consumers. The energy of a living organism cannot be gained or lost according to the first law of thermodynamics. The first law of thermodynamics explains that energy can neither be created nor can be destroyed.
So, the correct option is option D. Assertion is false, Reason is true.

Note: Ecosystems are not exempt from the second law of thermodynamics. They need a constant supply of energy to synthesize the molecule. They require counteracting the universal tendency towards the increasing disorderliness.