According to this lesson, which of the following languages did not influence Old English?

Before the Romans came to England, the British Isles were inhabited by the Celts (pronounced [kelts]), or Ancient Britons. But there are few obvious traces of their language in English today. Some scholars have suggested that the Celtic tongue might have had an underlying influence on the grammatical development of English, particularly in some parts of the country, but this is highly speculative. The number of loanwords known for certain to have entered Old English from this source is very small. Those which survive in modern English include brock (badger), and coomb (a type of valley), plus many place names. Their language - Gaelic - lives on to this day in Wales, Cornwall, Scotland and Ireland. It is not closely related to modern English. Celtic had very little influence on English and is mostly preserved in place names. Click here to read more about pre-Roman Britain (. pdf)