The primary focus of Data Science is Data Analysis. Data Analysis is the process of inspecting, cleaning, transforming, and modeling data with the goal of discovering useful information, informing conclusions, and supporting decision-making.
Data Cleaning is the process of identifying and correcting (or removing) errors in data. Data Visualization is the process of representing data in a graphical or pictorial format. Data Storage is the process of organizing and storing data in a way that makes it accessible and usable.
Data Analysis is the most important part of Data Science because it is the process of extracting meaning from data. Data Cleaning, Data Visualization, and Data Storage are all important supporting tasks, but they are not the primary focus of Data Science.