Emily has been evaluated by three different professionals, each of whom offers a different diagnosis. She wonders whether the field has any standards because their judgments obviously lack

Sense receptors are biological transducers, which means that they

a. select from a broad range of stimulation. b. analyze the environment into important features. c. convert one form of energy to another. d. detect only a limited range of energies.

As the child matures, the ability to focus attention selectively on particular activities tends to

a. weaken or diminish. b. show no systematic age trend. c. strengthen and improve. d. interfere with explicit memory, but help other skills.