Explanation
Privacy by design is an approach that embeds privacy principles and considerations into the design and development of products, services, systems, and processes that involve personal data. Privacy by design aims to protect the privacy and security of the data subjects, as well as to comply with the applicable privacy laws and regulations. One of the key principles of privacy by design is to obtain the consent and choice of the data subjects regarding the collection, use, and disclosure of their personal data. Therefore, the best example of privacy by design in the development of a consumer mobile application is to require consent before sharing locations, as this gives the data subjects control and transparency over their personal data. The other options are not as effective or sufficient as requiring consent before sharing locations, as they do not address the principle of consent and choice, or they may violate other privacy principles or requirements.
References: CDPSE Review Manual, 2021, p. 35