The correct answer is D. species.
The definition of a species is termed as a group of interbreeding individuals cannot be easily applied to organisms that they reproduce only or mainly by asexual methods.
Species is termed as the basic unit of classification and taxonomic rank and also unit of biodiversity. It is the largest group of organisms whereby two individuals produce fertile offspring.
They are typically by sexual reproduction. Boundary which is between closely related species they becomes unclear.
ANSWER FOR QUESTION 1:
The most common type of E. coli infection that causes illness in people is called E. coli O157, which produces a toxin known as Shiga-toxin. Shiga-toxin producing E. coli is abbreviated as STEC. Symptoms of infection with this germ include watery or bloody diarrhea, fever, abdominal cramps, nausea, and vomiting.
ANSWER FOR QUESTION 2:
Some other germs don’t cause as many illnesses, but when they do, the illnesses are more likely to lead to hospitalization. Those germs include: Anyone can get sick from eating contaminated food. Follow four simple food safety steps —clean, separate, cook, and chill—to lower your chance of food poisoning and to protect yourself and your loved ones.
A chromosome consists of a single, double-stranded DNA molecule. Chromatids are two molecules of double-stranded DNA joined together in the center by a centromere. Chromosomes have a thin ribbon-like structure. Chromatids have a thin and long fibrous structure.
Its hard to believe it but its D.<span />