The following are the characteristics of Cnidaria:
1. The organisms have specialized stinging cells known as cnidocytes.
2. Two types of body plans exist, that is, polyp and medusa.
3. The phenomenon of alternation of generation is observed.
The following are the characteristics of Porifera:
1. The organisms lack symmetry.
2. The adult forms are sessile.
3. The organisms obtain food by filtering water.
The answer is option C. Number of double covalent bonds between carbon atoms is responsible for causing different shapes of saturated and unsaturated fatty acids. The double covalent bond causes kink in the unsaturated fatty acids because of which their stacking is disrupted and they become loosely packed. The problem with double covalent bond is that unlike single covalent bond it can't rotate and has almost cis-configuration. This is also the reason behind their liquidity at room temperature.
I think the first one is right !.... but the for the other one it's B .
A large asteroid or comet impacted the earth.
