B that is the answer for this question
Many human illnesses are caused by infection with either bacteria or viruses. Most bacterial diseases can be treated with antibiotics, although antibiotic-resistant strains are starting to emerge. Viruses pose a challenge to the body's immune system because they hide inside cells.
The answer is the base sequence of gene's promoter.
DNA is a two-stranded helix. One strand is called a template strand, the other one is called a coding strand. The template strand is copied into mRNA, and the coding strand is complementary to the template strand. RNA polymerase, an enzyme responsible for transcription, has to recognize the right strand before transcription begins. So, it recognizes one or more short sequences on the coding strand. This is the base sequence of gene's promoter. Thus, the complementary strand is the template strand.
These cells consume bacteria and other pathogens to protect the body from infection. The process begins when chemicals from a pathogen, or damaged tissue, attract a phagocyte. The phagocyte binds to the microbe, envelopes it, and then eats it.
