One maternal and one paternal chromosome hook up with each other inside a cell during conception to form a pair of homologous chromosomes.

Concept: The above-given statement is true.

1. In a diploid (2n) organism, homologous chromosomes are two bits of DNA that carry identical genes from both parents, i.e., one from the mother and one from the father. 
2. This shows that an organism's entire genome is a product of both parents. 
3. Although identical chromosomes encode the same genes, they can also include various copies of each gene, which helps to diversify the population and keep it stable. 
4. Additionally, it lessens mutations' detrimental effects, some of which can be fatal. 
5. The homologous recombination procedure, which takes place during the meiotic cell division, also involves homologous chromosomes. 
6. When a portion of a chromosome is swapped between two gametes, the process is also known as crossing over between gametes.

Hence, option A is the correct answer.