Which piece of textual evidence best supports the inference that the germans could not lay new cables in the waters of the english channel?

Textual evidence is the evidence from the text that could support your statement or argument.

Try finding this in your text (since you didn't provide one) :

- There were 30 cable laying ships in 1896 and the british owned 24 of them, proving their market dominance
- During world war I, britain's telegraph communication almost flawless and uninterrupted, while Germany's cables were quickly cut world wide

hope this helps