Read through the following excerpt from "Inventions in the Century" by William Henry Doolittle.

"Neither the historic nor prehistoric records find man without musical instruments of some sort. They are as old as religion, and have been found wherever evidence of religious rites of any description have been found, as they constituted part of the instrumentalities of such rites. They are found as relics of worship and the dance, ages after the worshippers and the dancers have become part of the earth's strata. They have been found wherever the earliest civilizations have been discovered; and they appear to have been regarded as desirable and necessary as the weapons and the labor implements of those civilizations. They abounded in China, in India, and in Egypt before the lyre of Apollo was invented, or the charming harp of Orpheus was conceived.

There was little melody according to modern standards, but the musical instruments, like all other inventions, the fruit of the brain of man, were slowly evolved as he wanted them, and to meet the conditions surrounding him.

There were the conch shell trumpet, the stone, bone, wood and metal dance rattles, the beaks of birds, and the horns and teeth of beasts, for the same rattling purpose. The simple reed pipes, the hollow wooden drums, the skin drum-heads, the stretched strings of fiber and of tendons, the flutes, the harps, the guitars ... and hundreds of other forms of musical instruments, varied as the skill and fancy of man varied, and in accordance with their taste and wants, along the entire gamut of noises and rude melodies."

What is the central idea of this passage?

Musical instruments of the past were made out of a variety of objects.
The music of the past created very little melody.
Musical instruments were as vital a part of life for early man as the weapons and labor instruments.
Musical instruments were made out of whatever materials were available.

The central idea of this passage is that musical instruments were as vital a part of life for early man as the weapons and labor instruments.