What happened to the green active site of the protein in the mutated cftr protein

The role of CFTR is to build channels on the cell surface to enable the flow of chloride (Cl-). When the  CFTR protein works properly, the balance of Cl-and fluid at the cell surface is normal. If the mutation of  CFTR protein happens the balance of Cl- and fluids is disrupted, causing mucus in various organs to  become thick and gluey. As a result, lung infections and, eventually, respiratory failure in the lungs might  occur. Mutations on the CFTR normally change single amino acids in the CFTR protein which happens  in abnormal channel breaks down soon after it is made.

Explanation:

The CFTR gene gives direction for producing a protein called the cystic fibrosis trans membrane  conductance regulator. This protein functions being a channel over the membrane of cells that produce  mucus, sweat, saliva, tears, and digestive enzymes.The channel transports negatively filled particles  called chloride ions into and out of cells.The transport of chloride ions improves control the movement of  water in tissues, which is essential for the creation of thin, freely flowing mucus. Mucus is a slippery  substance that greases and defends the lining of the airways, digestive system, reproductive system,  and different organs and tissues.The CFTR protein further regulates the role of other channels, such as  those that transport positively charged particles called sodium ions across cell membranes. These  channels are essential for the normal function of organs such as the lungs and pancreas.

the correct option is option d