Which of the following effective opening techniques can immediately engage the audience and set the stage for an impactful presentation?a.Presenting a surprising statistic or fact that challenges conventional thinking     b.Employing a thought-provoking question that sparks curiosity and encourages reflection.c.Offering a brief preview of the key takeaways and benefits of the presentationd.Commencing with a personal anecdote that resonates with the audience's experiences.

All of the options mentioned can serve as effective opening techniques for a presentation.

a. Presenting a surprising statistic or fact that challenges conventional thinking: This can immediately grab the audience's attention and make them curious to learn more. It can also establish you as someone who brings fresh and unconventional perspectives.

b. Employing a thought-provoking question that sparks curiosity and encourages reflection: This can engage the audience by making them think and reflect. It can also create a sense of anticipation for the answers that will be provided in the presentation.

c. Offering a brief preview of the key takeaways and benefits of the presentation: This can help the audience understand what they can expect to gain from the presentation, which can motivate them to pay attention and engage with the content.

d. Commencing with a personal anecdote that resonates with the audience's experiences: This can create an emotional connection with the audience, making them more receptive to your message. It can also make the presentation more relatable and memorable.

Therefore, all of these techniques can be effective in engaging the audience and setting the stage for an impactful presentation.