Final answer:
Group polarization refers to the strengthening of a group's prevailing opinions after discussing them. Among the provided options, the statement that groups tend to make more extreme decisions by strengthening the original opinions of group members is true and best describes group polarization.
Step-by-step explanation:
Group polarization is the phenomenon where the strengthening of the original group attitude occurs after the discussion of views within a group. It explains why groups might make decisions that are more extreme than those made by any individual member. Regarding the statements:
Groups tend to make more extreme decisions by strengthening the original opinions of group members. This statement is true and reflects the definition of group polarization.
Groups always make more risky decisions than individuals: This is a misconception as the direction of polarization can either be towards risk or caution.
Group polarization has been lessened by the internet through broadening exposure to different opinions. Actually, the internet can increase polarization by allowing people to filter information that reinforces their existing views.
Group polarization provides a better explanation of the group decision-making process than groupthink. This is subjective and context-dependent.
Therefore, the first statement is the most accurate in describing group polarization.