All of the following are reasons why engraving can be difficult, except which?
a.
engraving requires a lot of pressure to be applied to the tool as it glides across the metal surface and the time it takes to complete.
b.
many artists struggle with the sound the tool makes while etching on metal.
c.
before beginning the engraving, the artist must apply a thin layer of acid to the metal surface on which the engraving will be done.
d.
when an artist creates an engraving, he must plan it carefully because mistakes cannot be corrected.

b. Many artists struggle with the sound the tool makes while etching on metal.

Explanation:

In the etching mode, the artist opens, with the help of an instrument known as a burin, several grooves in the metallic matrix. The chisel or chisel is a hand-held tool that has at one end a sharp and sharp metal blade, suitable for cutting or engraving wood, iron, among other materials.

The next stage of this technique is to lightly wet the paper; At this time the drawing is fixed and the image appears colored. This notching process is distinguished from others by the use of acids in the composition of the engraving. It is also possible to combine this procedure with other methods, such as dry tip.

In etching substances called mordants - nitric acid, iron perchloride, among others - invade the matrix regions that were not protected by the varnish, generating different cavities and thus multiple visual impressions. Through this mechanism the creator can produce the most varied shades and imagery contexts.

c.

Before beginning the engraving, the artist must apply a thin layer of acid to the metal surface on which the engraving will be done.