Fish poop.
Tropical white beaches get their pearly white color from the excrement of fish far off of the coast which eat coral and other things that reside on the ocean floor. When they eat they swallow some sand into their mouths as well, and process it with the food they just ate. Their stomachs can't really digest the sand, tiny minute rocks essentially, and thus turn their color white. Or the rock forming the sand can be naturally pigmented a whitish tone as well.
Answer:
the first question answer is C and for the second one is D
Answer AND Explanation:
A steroid is an organic macromolecule that is biologically active with four rings arranged in a specific molecular configuration. Steroids are important components of cell membranes which alter membrane fluidity and act as signaling molecules. The two main types of steroids are corticosteroids and androgenic steroids like testosterone and estradiol.
They are ineffective against viral infections because viruses can not be treated with antibiotics.