An experimental group is the group in an experiment that receives the variable being tested. One variable is tested at a time. The experimental group is compared to a control group, which does not receive the test variable. In this way, experimental groups are used to find answers in an experiment.
1 At around 9 months of age, babies begin to pull themselves up to a standing position. 2  By 10 months of age, a baby should be able to grasp objects with thumb and forefinger.
Color vision should be similar to that of an adult as well, enabling your child to see all the colors of the rainbow. Babies also have better eye-hand coordination at 4 to 6 months of age, allowing them to quickly locate and pick up objects and accurately direct a bottle (and many other things!) to their mouth.