Benjamin West was an (eighteenth-century) American artist (who) influenced British painters (just so much) as he did (other) American artists.
【正确答案】
C
【答案解析】短语搭配错误，应改为just as much。as...as...“和…一样…，像…一样…”，用来表示同级比较，其否定形式是not so...as...。该句是肯定句，所以用as...as...。