Final answer:
In the sentence provided, 'mountains' is the antecedent for the pronoun 'They.' Norway's mountainous terrain represented by antecedents like 'mountains' in sentences, impacts transportation, but investments in public transport are made to address such challenges.
Step-by-step explanation:
Antecedents are the words that pronouns replace or to which pronouns refer in a sentence. In the sentence 'Much of Norway is covered by mountains They make transportation difficult,' the antecedent for the pronoun 'They' is 'mountains.' The pronoun 'They' refers back to 'mountains', which is the noun that 'They' is replacing.
Norway's mountainous terrain does have a significant impact on transportation. The Western Highlands, extending through Norway, create challenging conditions for both transport and agriculture, with transportation being further affected by factors such as occasional obstacles in waterways as mentioned with the dam over the Carrying Place Inlet. However, despite these challenges, places like Oslo highlight investment in public transportation that helps navigate these geographical difficulties.