The authors indicated that sunscreen may be counterproductive because it does not screen out all UV. PLEASE NOTE: Sunscreens have been improved since the publication of this book; they filter UV much more thoroughly. It is now recommended by the medical community that sunscreen be used outdoors. Which are true (using current information)

a. Sunscreen decreases the risk of skin cancer.

b. Some sunglasses do not block UV. These are worse than no sunglasses with respect to developing cataracts.

c. The better predictor of skin cancer is the number of sunburns, rather than total UV exposure over one's lifetime.

Lyme disease is caused by a bacterium transmitted to people by deer ticks. deer ticks are almost never born infected with the bacterium, but they can pick it up from feeding on an infected host in any of the tick's three successive stage of development: larva, nymph, adult. once infected, a tick remains infected through any subsequent developmental stages, but since a tick feeds on only one host in each stage, it follows that . people can be infected only by being bitten by a tick that is either in larval stage or in the nymph stage b. people cannot be infected by a tick that picked up the lyme disease bacterium in the adult stage c. it is not possible for a person to be infected by a tick that is in the nymph stage or by a tick that was infected with the bacterium while in the nymph stage d. people infected with the lyme disease bacterium cannot transmit bacterium to adult deer ticks e. only deer ticks that are adults can transmit the lyme disease bacterium to people