Please explain why all the wrong answers are not the correct answer ( B is the correct answer btw)

Which of the following describes a negative feedback loop? when the heart rate is too high, the body sends hormones that continually increase the heart rate higher. when a pregnant woman is in labor, the body sends hormones that increase the intensity of contractions, which then increases the secretion of the same hormones. when blood sugar is too low, the body sends hormones that raise blood sugar until it reaches a typical level and hormone secretion slows. when a person is jogging, the body sends hormones that continually decrease the rate of oxygen supply to the legs.

The structure of a dna molecule is best described as a. one long strand of nucleic acids b. two strands of dna nucleotides joined by hydrogen bonds c. two strands of amino acids joined by hydrogen bonds d. one long strand of amino acids

The punnett square predicts the ratio of genotypes in the offspring, based on the genotypes of the parents. in this cross, tallness (h) is dominant to shortness (h). based on the punnett square, what is the phenotype of the offspring? hh hh tall short