請依下文回答第 46 題至第 50 題：
Nearly every single part of our body is made of living cells. And it’s these cells that help us see, breathe, feel, think andmuch more.   46   their jobs in the body may differ, one thing all these cells have in common is that they need energyto survive and perform their duties.
Cells need to turn nutrients in our diet into a form of energy that they can use, and the process starts with glucose. Glucoseis the basic fuel that powers every single one of our cells. If we eat or drink things that are high in glucose, the glucosegets absorbed straight into our blood ready for our cells to use. If a starchy food is   47   the menu, the enzymes inour saliva and digestive juices break it down and convert it into glucose. And if for some reason there’s no carbohydratein our diet, cells can turn fat and protein into glucose as a last   48   , because they need glucose to survive.
It’s here that sugar and cancer start to   49   , because cancer is a disease of cells.
Cancer cells usually grow quickly,   50   at a fast rate, which takes a lot of energy. This means they need lots ofglucose.
 All our healthy cells need glucose too, and there’s no way of telling our bodies to let healthy cells have the glucose theyneed, but not give it to cancer cells.
【題組】46
(A) While
(B) Because
(C) If
(D) As