Choose the best answer. IQ scores of identical twins tend to be more alike than those of same-sex fraternal twins. This might be taken as very good evidence for a hereditary effect. Parents treat identical twins more alike than they do fraternal twins. Identical twins are typically born into middle-class families, where they both are provided with stimulating environments.
Identical twins tend to have similar achievement test scores.
In the development of babies babbling, it can be said that they are learning the words before the tune . When babies babble with a falling intonation at the end of a string of sounds, it seems to signal a desire for a response. When babies first start babbling, they typically babble all kinds of sounds, including some that are not part of the language they are hearing. At about 11 or 12 months of age, the sound repertoire in babbling gradually comes to include many sounds babies do not hear spoken around them. Children generally understand more than they can express.