I would say the correct answer is that has an undetermined answer.
If a subject has been thoroughly covered, then there is no need for this researcher to do it all over again. If it's impossible to answer, there is no need to try. If it can be answered easily, then it doesn't really require a research. This leaves us with the last option, because a researcher might want to try and determine the answer.
Jack and I - we
Books - it
Sister - she
You and Dave - they
Plane - it
Sunshine - it
Cheese - it
Cactus - it
Parents - they
Pamela - she
News - it
Scissors - they
Geese - they
Flowers - they
Piano - it
School - it
Daughter - she
Milk - it
Children - they
Sugar - it
Feet - they
Bicycle - it
Ann and Kate - they
Tennis - it
Son - he
Mice - they
Sky - it
Shop - it
Buses - they
Papers - they
Mr. Green - he
Brother-in-law - he
Picture - it
Friendship - it
Dolphin - it
The Ringgs family - they
Answer:
That fire can put out fire.
Explanation:
