B. They have tentacles with stinging cells is a common characteristic of cnidarians.
<span>Density-dependent factors, however, are those that have great impact only once populations reach a certain level. A flood or some other natural disaster may affect them by decreasing the rate of these factors on having an effect to the society. Hope this helps. Have a nice day.</span>
The white blood cells attack the infection
B. Hydrogen bonds make the positive sides of water molecules stick to each other