Which of the following are considered the fundamental building blocks of life?

The fundamental building blocks of life are primarily based on their roles in biological systems and their structural significance. Cells are considered the basic unit of life; they form the foundation upon which all living organisms are built. Tissues, while essential for the organization of cells into functional groups, are not the smallest unit of life and therefore are not regarded as foundational blocks in the same way that cells are.

DNA and RNA, which are both crucial for genetic information and protein synthesis, represent the key molecules that encode the instructions necessary for life. DNA, or deoxyribonucleic acid, contains the hereditary information, while RNA, or ribonucleic acid, serves as a messenger and plays a vital role in translating genetic information into proteins. The option referencing DNA and RDNA—though perhaps highlighting a broad aspect of genetic material—is distinct in that RDNA typically refers to recombinant DNA, which is a synthetic combination of DNA from different sources. While this is significant in genetic engineering and biotechnology, it does not encapsulate the fundamental components of life on a foundational level.

Proteins and carbohydrates are essential molecules within biological systems, but they are not standalone building blocks of life. They are largely products of the processes defined by the DNA and RNA. Proteins serve