question:  Why are the police studying Frownes so intently?
context: In the ensuing contretemps they emptied his rear pants pockets, got his wristwatch and restored the contents of the handkerchief pocket. It was this rather than skill that enabled the police to maintain such a tight surveillance on him, a surveillance that went to the extent of getting his fingerprints off the postman's bag, and which photographed, X-rayed and chemically analyzed the contents of his pockets before returning them. By the time Fownes reached his front door an entire dossier complete with photographs had been prepared and was being read by two men in an orange patrol car parked down the street. It was similar to that of a pathologist observing for the first time a new and particularly virulent strain of pneumococcus under his microscope. Lanfierre's job was to ferret out aberration. He came to see that genuine quirks were rare and, as time went on, due partly to his own small efforts, rarer. After years of searching for differences Lanfierre had seen how extraordinarily repetitious people were, echoes really, dimly resounding echoes, each believing itself whole and separate. "You're starting to see flying houses, hear loud babbling voices. MacBride and Lanfierre both leaned forward, as if waiting for the ghostly babble of voices to commence. It expressed his weariness and distaste for people who went off and got neurotic when they could be enjoying a happy, normal existence. Fownes stopped on the porch to brush the plaster of paris off his shoes. Or, as Fownes hoped it might appear, the illusion of the domed city vanished and was replaced by a more satisfactory, and, for his specific purpose, more functional, illusion. Instead of an orange sun at perpetual high noon, there was a red sun setting brilliantly, marred only by an occasional arcover which left the smell of ozone in the air. The sun and moon both looked down upon a garden that was itself scintillant, composed largely of neon roses.
output:  They are suspicious of the odd behavior occurring within and around his home
options:  They are threatened by his knowledge of and curiosity about the ancients  They are suspicious of the odd behavior occurring within and around his home  They believe he is responsible for the increased frequency of falling glass  They believe he is an informant to enemy forces outside of the Dome