Answer:
The answer is DNA and RNA.
Explanation:
Because they work with each other during the process of protein synthesis, such as storing and transporting cellular information. They have no direct relationship because they are diffent, have different roles during the process, but their separate work complement each other and function perfectly.
When the question says: free efficient expression binds them, the question reffers to gene expression, which is a process that allows the obtainicy of proteins from genes. The process ends with the protein synthesis, where occurs the DNA and RNA binding.