Answer:
Option A, Hormones are controlled by a feedback loop; information about a system is sent back to the controller of the system to improve its function.
Explanation:
Negative feedback loop controls the hormone production and release. This is done by eliciting the release of substances till a certain level after which the stop signal is activated thereby preventing further release. By this method, concentration of hormones in blood is maintained within the narrow range.
For example – Thyroid hormones is released when the anterior pituitary signals the thyroid. This continues till the hormones in the blood reach the threshold level. Once the threshold level is reached, hypothalamus receives a feedback and then signals anterior pituitary to inhibit further signaling to the thyroid
Hence, option A is correct
B. Methane (Ch2) is released by animals and contributes to global warming
In order to calculate the distance between two alleles/genes that are found in the same chromosome, we need to know how often crossing-over happened (recombination frequency). We know from the text that white eyes were linked to miniature wings and that wild type eyes were linked to wild type wings, so any phenotype that's contrary to these parent combinations are a result of crossing-over. We know then that 230 flies + 240 flies were a result of such recombination. To calculate the recombination frequency we only need to divide these flies (total of recombinant flies) by the total of flies in the offspring and turn it into percentage.

=0.47
0.47*100%=47%
47 map units is the distance between the genes <span>for eye color and wing length.</span>