Answer:
The correct answer would be (3) genes in an egg cell.
Evolution is the process by which genetic makeup or composition of a population gradually changes over a number of generations.
It could take place due to the number of factors such as natural selection, a mutation in germ cells, genetic drift, inbreeding et cetera.
It leads to the change in the heritable characters of a population which may or may not provide survival adaptations to the population.
As we know, only germ cells take part in the production of gametes (egg or sperm) and responsible for passing genetic material from one generation to another.
Hence, change in genes in an egg cell can pass from one generation to the next and can cause evolution.
Other cells such as muscle cells, liver cells, bone cells, et cetera are called as somatic cells which do not take part in the formation of gametes and thus they do not transfer their genetic material from parents to the offspring.
Hence, any change in the sequence of somatic cells would not result in the evolution.
