Final answer:
The subject of this question is Biology, specifically DNA strands and their importance in various fields such as genetics, medicine, and bioinformatics.
Step-by-step explanation:
The subject of this question is Biology. DNA strands are a fundamental concept studied in biology. DNA stands for deoxyribonucleic acid, which carries the genetic information of an organism. It plays a crucial role in fields such as genetics, medicine, and bioinformatics.