1. An imaging apparatus comprising: an imaging unit configured to generate RAW image data representing an undeveloped image which is captured by an image sensor in response to a capturing instruction; a development unit configured to generate image data by applying, to the RAW image data, a first development process or a second development process that can provide an image having higher image quality than that obtained by the first development process; a recording unit configured to read and write data from and to a recording medium; and a control unit configured to control the recording unit so as to write, to the recording medium, the RAW image data and first image data obtained by applying the first development process to said RAW image data, and thereafter control the development unit and the recording unit so as to generate second image data by applying the second development process to the RAW image data written to the recording medium and write the second image data to the recording medium, wherein the control unit is further configured to: control the development unit so as to generate a plurality of pieces of third image data from the RAW image data by using a plurality of different development parameters; and decide, from among the plurality of pieces of third image data, a development parameter corresponding to image data selected by a user as a development parameter used in a development process for the RAW image data that is applied after the RAW image data has been written to the recording medium.