Read the following passage and questions, then choose the right answer from options, the answer should be one of A, B, C, D.

<passage>:
If you haven't visited a dentist in the past few years, first of all, that's gross. (Checkups are every six months, and don't pretend you forgot.) Second, be grateful that you have avoided the "intra-oral camera." As the dentist (or assistant) navigates this horrifying little gadget through the graveyard of your mouth, a color television magnifies the florid pustulance of your gums and the puke-yellow dinge of your smile. A harmless crevice in your silver-mercury amalgam filling looks like Hell's Canyon. The microcracks in your enamel look like a broken window. All this can be fixed, of course, with 10 grand of straightening, filling, sealing, and whitening. "You will agree to anything the second they put that thing in your mouth," says one recent victim of the camera. "You can't believe you are walking around with that, that, that ick in your mouth." The transformation of American dentistry from drill-and-fill to shoot-and-loot is an unlikely business success story of the '90s, a case study in how a profession can work itself out of a job and still prosper. Dentists, after all, are supposed to be extinct by now. While they happily (and profitably) scraped teeth and filled cavities during the '60s and '70s, fluoride was quietly choking off their revenue stream. The percentage of children with cavities fell by half and kept falling. People stopped going to the dentist, because they didn't need to. At the same time, the government funded dental-school construction, spilling new dentists into a saturated market. Many found themselves cleaning teeth for $10 an hour in mall clinics. In 1984, Forbes magazine forecast the end of the profession. Only a few lonely dentists would survive to fill the few remaining cavities, the last vestiges of a once-great civilization on Long Island. The most important discovery dentists made was the endless vanity of aging baby boomers. "We are dealing now with the boomers who are the runners and the joggers and the dieters, and they are very concerned with how they look," says American Dental Association President Dr. Timothy Rose. Since going to the dentist was no longer a necessary evil, dentists made it an unnecessary pleasure. They allied themselves with the self-improvement movement. "You still go for the needs, for the cavity that has to get filled, but more and more people ... come here to feel better about themselves," says Dr. Stephen Friedman, a Maryland dentist. People used to be happy if they made it to old age with enough choppers to chew. But boomers, lured by media images of the Great American Smile, expect more. According to an ADA poll, the percentage of people who are "very satisfied" with their teeth has dropped from 57 percent to 46 percent in the past decade. Dentists have learned to play on this vanity and anxiety, encouraging dental care that is medically unnecessary but attractive to patients. "It's as if you went to a physician for a treatment for a disease and he said you needed a nose job," says Dr. John Dodes, author of Healthy Teeth: A User's Manual . This hard sell is critical in dentistry in a way that it isn't in other medicine because of the profession's brutal economics. Dental insurance covers only 44 percent of Americans (compared to more than 80 percent for health insurance), and provides skimpy coverage for those who do have it. As a result, patients pay most dental costs--about 60 percent of them--out of their own pockets. Dental care is just another way to spend discretionary income, competing with a vacation or a new car. Dentists have to make patients want adult orthodontics in a way physicians don't have to make patients want a quadruple bypass. It's tempting to dismiss the whole industry as a scam, particularly when dentists keep coming up with new ailments such as bruxism (teeth grinding), periodontal disease, malocclusion (bad bite), and microcracks. But these ailments are real, and our awareness of them shows how far dentistry has come. A generation ago, dentists filled teeth and cast dentures because that's all they knew. Decay killed so many teeth that fancier problems seldom arose. Since then, researchers have studied bonding, implants, and periodontal disease. Dentists can now make crowns that last forever, bridges that stay anchored, dentures that behave almost like real teeth. A generation ago, implants were a joke. Today's implants, affixed to your jawbone by a titanium screw, can hold for the rest of your life. Scientists have learned how bacteria can build up in gaps in the gum, cause infection, weaken the jawbone, and eventually murder teeth. New research links these periodontal bacteria to heart disease, diabetes, low birth-weight babies, and other nastiness you'd expect from bacteria running wild in the bloodstream. This is why your dentist hectors you to rubber-tip your gums, brush with a superconcentrated fluoride toothpaste, and wear a night guard to control your bruxing (which loosens teeth, opening pockets between teeth and gum, etc.). It's also why your dentist may bully you into gum surgery. It all seems unpleasant and slightly absurd--the night guard is "an excellent form of birth control," as one wearer puts it--but the alternative is losing your teeth at 40, getting dentures, and gumming your food. Dentistry is a hassle now because it works. "If you think back a couple of generations, it was considered inevitable that people would lose their teeth when they reached midlife. Around 40 or 45, you would have your teeth taken out. Periodontal disease was not understood, and decay was rampant. But now teeth are resistant to decay and are lasting a lifetime. I have gone in 18 years from learning how to make dentures and thinking it is OK for people to lose teeth to being appalled if anyone loses teeth. It is a failure," says Dr. Judith Penski, my own fabulous D.C. dentist. Which brings us to the irony of dentistry's comeback: Just as patients love the dental care they should suspect, they resent the care they should appreciate. Aesthetic dentistry is the most profitable segment of the business because it is an easy sell. Put a camera in your mouth and you'll want whiter teeth, too. It is much harder to convince someone to poke her gums every night with a piece of rubber, to sleep with a choking plastic tooth guard, and to undergo four surgeries to fix a gum flap, all for a benefit that is decades away. The very success of dentistry has raised expectations so high that patients now object to any inconvenience. Americans under 60 believe keeping all their teeth is an entitlement: Telling them they need gum surgery to preserve their teeth makes them angry, not grateful--even though those teeth would have been goners 20 years ago. When I surveyed 100 friends and acquaintances about their dental complaints, few bitched about cosmetic dentistry that was foisted on them. They like their whiter, straighter teeth. No, they griped about the medically advisable treatments that their dentists prescribed, especially gum surgeries and mouth guards. Pity the poor dentist who abjures cosmetic dentistry but vigorously protects patients' teeth. Patients don't like periodontal treatment, so they suspect it's a rip-off. This could not be further from the truth. Such is the triumph of American dentists: If they can't sell you what you need, they'll sell you what you want.

<question>:
How do modern dental procedures compare to those of the past?

<options>:
A There are less options available
B They are more temporary
C They are more permanent
D They are more comfortable

<answer>:

C