Final answer:
Acceptance of decisions is typically higher in group decision-making due to the collaborative nature of reaching a consensus. However, groupthink can negatively impact decision quality, and while group decision-making processes involve shared responsibility, they cannot fully avoid diffusion of responsibility.
Step-by-step explanation:
The question pertains to the nature of group decision-making and its outcomes relative to individual decision-making. The aspects to consider are the speed of decision-making, acceptance of decisions, the possibility of groupthink, and the diffusion of responsibility. When decisions are made in a group setting rather than individually, the process generally takes longer due to discussion and the need to reach a consensus, which means option (a) is generally not true. However, due to the collaborative effort and shared ownership over the decision, acceptance of the decision is typically higher, which makes option (b) most accurate. Groupthink is a phenomenon that can negatively affect the quality of decisions, thus refuting option (c). As for option (d), it is challenging in a group context to entirely avoid diffusion of responsibility since contributions are distributed among multiple individuals, with no single person being fully accountable.
Collective action problems are indeed less severe in small groups, due to the factors mentioned in option (d) - individuals are less able to free ride, it is easier to monitor individual behavior, and peer pressure is stronger. It's also essential to implement tactics to prevent groupthink, such as seeking outside opinions and having open discussions that allow for diverse viewpoints. By contrast, transaction costs and the challenges of coordination could be higher in group decision-making. Decisions could be biased towards the status quo (option a), majority or supermajority rules, or require compromise. Informational social influence can also affect decision-making within groups, especially when individuals are uncertain or perceive the group as having expertise (options b and c).