"To help foster peace and economic collaboration among European nations" is the one among the following choices given in the question that <span>best describes the purpose of the European Union. The correct option among all the options that are given in the question is the first option or option "A". </span>
The correct answer is - C) carotenoids.
The majority of the trees from the mid-latitude forests tend to shade their leaves in the autumn. This process occurs because of the seasonal changes in the climate, where the trees tend to be almost not-active during the winter, so in order to preserve as much energy and nutrients as possible they get read off their leaves.
It is not a sudden process, but it takes some time, where the leaves from the initial green color start to change to yellowish, than towards orange, reddish, or brownish before they fall.
The reason why this coloration appears in the leaves when the tree starts to process of shading them off are carotenoids. The carotenoids found in the leaves, the lutein and the beta-caroten, thorugh the xantophills and the flavonoids give a yellowish color to the leaves, thus we get the beautiful autumn colors and landscapes.
Objects with like charges repel/repulse each other while opposite charges attract each other
The direction of an electric fields is alway the direction electrons would naturally move.
Not sure about the last one, my gut instinct is opposite.
Keystone species, they kinda hold the food webs together