Mrs. Martin, a third grade teacher, is teaching cursive writing. At first, she reinforces even crude attempts to reproduce letters with an encouraging word; as time goes on, though, she reinforces only well-formed letters. By reinforcing progressively better attempts at writing letters, Mrs. Martin is using:

A major reason why the body of a 6-year-old more closely resembles an adult's body than a toddler's body is because the child's center of gravity has dropped from the breastbone to the belly button

Indicate whether this statement is true or false.

Partial, or __________, reinforcement is a method in which responses are sometimes reinforced and sometimes not

a. trace b. porous c. delayed d. intermittent