Group of tissues performing a specific task is known as organ and group of organs performing a specific task is organ system.
I think the first one is right !.... but the for the other one it's B .
Those small sections are called Genes
A star’s life expectancy depends on its mass. Generally, the more massive the star, the faster it burns up its fuel supply, and the shorter its life. The most massive stars can burn out and explode in a supernova after only a few million years of fusion. A star with a mass like the Sun, on the other hand, can continue fusing hydrogen for about 10 billion years. And if the star is very small, with a mass only a tenth that of the Sun, it can keep fusing hydrogen for up to a trillion years, longer than the current age of the universe.
The correct answer is lipase activity in the large intestine.
Triglycerides are the main components of body fat and human skin oils. Lipases are enzymes which break down the fats or lipids in the body. They are responsible for the digestion and general processing of triglycerides. There are several different lipases in the human body, pancreatic lipase acting in the small intestine, hepatic lipase, lipase acting in the endothelium and lipase in the bile acid.