Final answer:
The St. George's Cross flag would have been raised for the Shakespearean play Measure for Measure, as this was the convention in the Globe Theatre to indicate a play performance.
Step-by-step explanation:
The flag that would have been raised for the play Measure for Measure is b) St. George's Cross. This is because the typical convention during the time of Shakespeare's plays at the Globe Theatre was to raise the St. George's Cross to signify a performance of a play.
Since Measure for Measure is a Shakespearean play, this would have been the flag raised, not the Union Jack, The White Ensign, or the Jolly Roger, which have different associations and were used in other contexts. The Jolly Roger, for instance, is commonly known as the pirate flag, and the Union Jack represents the United Kingdom as a whole.
The flag that would have been raised for the play Measure for Measure is St. George's Cross. This flag is the national flag of England and features a red cross on a white background. It is associated with England and is often used to represent the country in various contexts.
Therefore answer is b) St. George's Cross.