Answer:
The statement C that says ''is derived from the inner cell mass'' is false.
Explanation:
The trophoblast is a structure composed of a set of cells (cytotrophoblast and syncytiotrophoblast), which are shaping the outer layer surrounding a blastocyst, during the earliest stages of embryonic development that mammals pass.
The trophoblast provides nutritive molecules to the developing embryo and facilitates its implantation to the uterine wall due to its ability to erode the tissues of the uterus, that is, it is responsible for making it possible for the embryo to be implanted in the uterine endometrium. Thus, the blast can join the cavity formed by the uterine wall, where it will absorb nutrients from the fluid from the mother.
During the third week, embryonic development includes the development of the trophoblast. At the beginning, the primary villi are formed by the internal cytotrophoblast which is surrounded by the outer layer of syncytiotrophoblast. Then, the cells found in the embryonic mesoderm are directed to the primary villous in the third week of gestation and when it ends, the mesodermal cells begin to be singled out to form blood vessel cells. 
 
        
             
        
        
        
Hey There! Hope you are having a GREAT day!
Your question was.... "What layer of the blood vessel wall is composed of areolar connective tissue containing elastic and collagen fibers"
Your answer is the Tunica intima, Because, The blood vessel's tough outer layer is made up of connective tissue, which permits it to withstand stresses occurring on the vessel wall. It also contains strong collagen fibers that help bind the blood vessel to surrounding tissues, providing stability to the vessel.
I really hope this helps! :)
 
        
             
        
        
        
The flower mechanism that would not help them preventing pollination by a specie such as a foreign plant would be that the flowers of different species are then the same color and would attract the same pollinators.Hope this would be of help.