The correct option is A.
The nature is organized in such a way that, one organism's waste is what the other organism will use as its own resources. For instance, during the process of photosynthesis, the oxygen that is produced as the by product of the photosynthesis process is what humans use to carry out their own breathing process.
Answer:
The correct answer is- Normal vaginal pH is acidic (4 to 5), which protects from infection.
Explanation:
The vaginal part in woman have high tendency to get infection because of moist internal condition and its location but vagina also have a protective mechanism which protect it from the infection.
A woman's vagina contains many species of Lactobacillus genus which secrete lactic acid and hydrogen peroxide that maintains the low pH level in the vagina. So due to this reason, the normal pH of the vagina remains between 4-5 which does not allow pathogenic bacteria to flourish and cause infection.
The HCG hormone is the answer possibly
For many species, there are often regional differences in their genes, although most of the time this differences aren't noticeable in their outward appearance.
So basically water is a polar molicule. So when it comes to the structure, water is able to form many hydrogen bonds and the way the atoms are able to bond together adds to the water's special properties.