You are very filial. Taking your parents on a trip is a great thing! For you, I think a small group of 5 people may be more suitable.
Although the cost may be lower if you travel with a large group, it may be noisy if there are too many people, and it will be difficult for the tour guide to take care of everyone. You have 10 days. A small group of 5 people allows you to arrange your itinerary more freely and enjoy the travel process better. Moreover, small group tour guides can also serve you more attentively, making your tour more comfortable and enjoyable.

Of course, which method to choose depends on your personal preferences and budget. If you like the excitement and don’t mind traveling with strangers, then a group of 20 people is also a good choice. However, no matter which method you choose, be sure to choose regular travel agencies and tour guides to ensure the safety and quality of travel.  

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