Classify the relation of question with context to one of these categories: 1) award received, 2) based on, collection, 3) conflict, 4) constellation, 5) convicted of, 6) date of death, 7) director, 8) drafted by, 9) educated at, 10) medical condition, 11) military branch, 12) narrative location, 13) occupation, 14) original network, 15) parent company, 16) point in time, 17) production company, 18) residence, 19) series, 20) service entry, 21) sex or gender, 22) spouse, 23) standards body question.
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Question: Context : The Paveway IV entered service with the Royal Navy in 2008. 
Question : Which was the official year for the approval of Paveway IV?

Answer: service entry


Question: Context : Prom-asaurus attracted 6.67 million American viewers during its initial airing and received a 2.7/8 Nielsen rating/share in the 18--49 demographic, up significantly from the 2.5/8 rating/share and 6.01 million viewers of the previous episode, ``Choke'', which was broadcast on May 1, 2012. 
Question : What is the series that Prom-asaurus is a part of?

Answer: series


Question: Context : Francis Fessenden was born in Portland, Maine, in the spring of 1839. 
Question : What was the military branch for Francis Fessenden?

Answer:
military branch