The main function of the nematocyst is prey capture. The correct option among all the options given in the question is option "B". The nematocysts are used by Cnidarians like hydra, jellyfish etc. It is actually a specialized capsule that contains venom and it is used to paralyze and capture small preys for food and also to sting any enemy that comes near.
Answer:
As the food moves through the gastrointestinal tract, and when it reaches the duodenum via the stomach, the food or the paste, that is, chyme becomes acidic because of the presence of acid in the stomach. When this acidic chyme moves towards the first section of the duodenum, it results in the discharging of cholecystokinin and secretin from the duodenal mucosa, which further instigates the pancreas to discharge alkaline pancreatic juice that comprises pancreatic enzymes and bicarbonate ions.
Now the bicarbonate ions will turn the chyme alkaline and is now known as chyle. It is made alkaline as the pancreatic enzyme needs alkaline pH to function on food. The intestinal juice is also secreted due to the discharging of similar hormones as mentioned above. However, the difference is that both the mechanical stimulus and nervous stimulus results in the discharging of intestinal juice, though it is not true for pancreatic juice.
Answer is Crescent
When the Moon appears smaller than a quarter, we call it a crescent. When the Moon appears larger than a quarter, we call it gibbous. When the moon is getting bigger (phases New to Full) it is waxing. When it is getting smaller (phases Full to New) it is waning.
I believe the answer is tertiary