In the Pretest- Posttest Control Group Design Shown Above, Selection

question 60

Multiple Choice

$\begin{array} { l l l l l } \mathrm { EG } : & \mathrm { R } & \mathrm { O } _ { 1 } & \mathrm { X } & \mathrm { O } _ { 2 } \\\mathrm { CG } : & \mathrm { R } & \mathrm { O } _ { 3 } & & \mathrm { O } _ { 4 }\end{array}$ In the pretest- posttest control group design shown above, selection bias is eliminated by _ .

• A) randomization
• B) matching
• C) statistical control
• D) design control

---

Definitions:

Search for an Object

A cognitive milestone in child development where a child learns that objects continue to exist even when they are not seen, leading to behaviors such as looking for hidden objects.

Problem Solving

The process of identifying a challenge and finding an effective solution to overcome it.

Final Substage

The last phase or period in a series of developmental stages or processes, indicating the completion of a certain developmental sequence.