The correct answer is: Heartburn often results when the gastroesophageal sphincter fails to close properly.
The gastroesophageal sphincter is a muscle located at the bottom of the esophagus that has to be relaxed in order to allow food to flow down into the stomach. After it contracts (tightens), the food and the stomach acid can’t flow back up into the esophagus.
When the gastroesophageal sphincter fails to close properly acid reflux occurs and causes the heartburn.
 
        
             
        
        
        
When river water<span> meets </span>sea water<span>, the lighter </span>fresh water<span> rises up and over the denser </span>salt water<span>. </span>Sea water<span> noses into the estuary beneath the outflowing </span>river water<span>, pushing its way upstream along the bottom. Often, as in the Fraser </span>River<span>, this occurs at an abrupt </span>salt<span> front</span>
        
             
        
        
        
Substrate-Level Phosphorylation is a mode of ATP synthesis that occurs when an enzyme transfers a phosphate group from a substrate molecule to ADP. 
This is from my AP Bio notes. Not 100% sure, but it does sound the closest in comparison to other processes.
        
             
        
        
        
Answer:
I think it's a gas.
Explanation:
Well, I'm pretty sure it's gas. Solid, liquid, gas. A liquid that's too cold becomes solid. Too hot becomes gas.
 
        
             
        
        
        
Ans. (B). '
Since iron is required to make hemoglobin and myoglobin, iron deficiency decreases the amount of oxygen in the blood and in the muscles.'
Anemia represents deficiency of blood cells to deliver sufficient oxygen throughout the body organs. Myoglobin and hemoglobin are oxygen-transporting proteins, present in muscles and red blood cells, respectively. 
Both these proteins are made up of polypeptide chains and heme groups. The heme group contains iron, hence, iron-deficiency causes insufficient amount of myoglobin and hemoglobin. Due to this, the amount of oxygen decreases in muscles and blood and leads to anemia. 
Thus, the correct answer is option (B).