The answer would be fossils since they are they remains of past life forms
B. sexual selection, which alters allele frequencies in the gene pool.
The RNA (ribonucleic acid) and the associated proteins forms the ribosomes. These ribosomes are the site of protein synthesis in a cell. Inside the stained cell nucleus, the nucleolus part of the cell can be seen. The nucleolus is the part where the all the ribosomes of the cell are assembled.
Hence, the answer is 'nucleolus'.
The nucleus is an organelle found in eukaryotic cells. Inside its fully enclosed nuclear membrane, it contains the majority of the cell's genetic material. This material is organized as DNA molecules, along with a variety of proteins, to form chromosomes.