A flock of Canada geese suddenly appeared in the yard

Find the personal phrase, subject and verb.

I'm not sure if I've ever heard of a "personal phrase", but the prepositional phrase, would be "in the yard", the subject is geese, and the verb is appeared.

The final option is the correct one - "technical language should be eliminated and visuals should be added". The broader audience is certainly not familiar with all the technical terms, and if every word in the manual was technical, they wouldn't understand a thing. Whereas if those words are omitted, it is likely if will be easier for them to grasp the meaning. And of course, everything is easier if there are pictures involved.