Question

_____ whole system is corroded with corruption from ____ top
to ______ bottom.

Answer 1

The whole system is corroded with corruption from top to bottom.

Articles:

There are two kinds of articles in English grammar.

1) Definite article (The):

• The definite article "The" is used before a specific singular noun.

2) Indefinite article (A/An):

• Article "A" is used before an unspecific singular noun that begins with a consonant sound.  
• Article "An" is used before an unspecific singular noun that begins with a vowel sound.

Answer 2

a whole system is corroded with corruption from a tap to an bottom