Probably because they wanted to.
Answer:
<em>niceee!~ Have a great day~</em>
<em>~Keiji❤</em>
<em>Please remember to eat, you are valid and someone loves you~!</em>
<em />
Explanation:
Notice that this picture shows a bass clef.
The notes are F, C, G, B.
That's the<em> first choice</em> on the list.
<span>If one scans topics and pages of Leonardo da Vinci's notebooks, it becomes apparent that he kept them strictly for his own use. The correct answer is D. He never intended to actually publish those works, at least until he achieved definitive results in what he was studying. He wanted to experiment a lot and was interested in many scientific things, many of which could be found in his notes.</span>