The answer to this question is Imagery
In option C all the words are a form of the verb "to be"
were: simple past,
be: infinitive
been: past participle
being: present participle
so this is the correct answer, as "to be" is a helping verb<span />
Answer:
The International Astronomical Union (IAU) downgraded the status of Pluto to that of a dwarf planet because it did not meet the three criteria the IAU uses to define a full-sized planet. Essentially Pluto meets all the criteria except one—it “has not cleared its neighboring region of other objects."
Explanation:
Encryption software has been used by the military