Answer:
Parliament
Significant
Power
reign
Step-by-step explanation:
The four keywords that best illustrate and summarize the sentence are (Parliament; Significant; Power; reign). The sentence describes the boosting of significant power of parliament during the reign of Henry VIII. The key focus here is that the parliament gained power in the reign of King Henry VIII. So, the keywords would be as mentioned above in order to display the major idea and thought of the statement.