The correct answer is: under.
The word “under” is used to indicate that something is done or happens in accordance with a particular authority or power. In this case, the company is manufacturing the product under the license of the parent company. This means that they have permission from the parent company to manufacture the product and that they are subject to the parent company’s rules and regulations.
The other options are not correct because they do not convey the same meaning. The word “about” is used to indicate that something is concerned with or related to a particular topic. The word “in” is used to indicate that something is located or contained within a particular place or area. The word “of” is used to indicate that something is a part of or belongs to a particular group or category.
In conclusion, the correct answer is “under” because it is the only option that conveys the meaning that the company is manufacturing the product in accordance with the parent company’s authority.