An experiment is a research method in which the investigator manipulates the ______variable and observes whether any changes occur in a(n) ______ variable as a result

The simplest evidence of learning in infants is the phenomenon of __________

a) rooting. b) habituation. c) reflexes. d) temperament.

Which of the following places gross motor development tasks in their proper order?

A) hold head up, sit upright, roll over, crawl B) hold head up, roll over, sit upright, crawl C) roll over, hold head up, sit upright, crawl D) hold head up, roll over, crawl, sit upright