A testable question is something you need data for, ex: if i bounce a bouncy ball from larger heights, how high will it fly? it can't be just a regular yes or no question
This answer will vary a lot, depending on who you will ask. If you're asking proponents of the LCHF (low carbs, high fat) diet, they would say you should reduce your intake of carbohydrates down to around 10 to 20 percent, making either A or C your desired answer.
If you would ask people who propose the current nutritional guidelines as the best way of eating, the amount of caloric intake that should come from carbs according to them would be more in the range of around 40%, making B the correct answer.
There isn't really any clear cut answer here.
The correct answer is B, internal intercostal muscles and abdominal muscles would contract.
Exhalation is the flow of the breath out of the body. During forced exhalation, internal intercostal muscles contracts which lower the rib cage and decrease thoracic volume, while the abdominal muscles push up on the diaphragm which causes the thoracic cavity to contract.
Food is mixed with protease is the correct answer. Hope this helps :)