If you search this on google the answer will come up.
<span>The answer is A. Food has been, since the emergence of life
on earth, the first source of energy for organisms. This energy was harnessed through
respiration to enable growth and development, movement and also provide heat. Ancient
humans then discovered fire and also harnessed its energy to cook food (making food
easily digestible) and also warming themselves during winter. </span>
Its more logical to say a leaf tissue because of the presence of several tissues inside it which are performing their designated functions.
<h3><u>Explanation:</u></h3>
If we look at the cross section of a leaf, the leaf tissue looks having several tissues. There are vascular bundles in the midrib that are xylem and phloem. Then there are leaf parenchyma which contains the chloroplasts.
They are palisade parenchyma on upper layer and spongy parenchyma. Then there are leaf epidermis on both upper and lower surfaces of leaf. So because of the presence of different tissues, they are collectively called as leaf tissue.
You would expect a scratch on the quartz since quartz is on a hardness scale of 7 and the mineral you are rubbing against it is at a hardness scale of 7.5
