Which statement about data types is correct?

Unstructured data is indeed the hardest to query but the most flexible in terms of its format and structure. This type of data does not adhere to a predefined model or schema, which means it can come in various forms, such as text, images, audio, and video. Because there is no strict structure, unstructured data can contain a vast amount of information, which allows for greater flexibility in how it can be stored and processed, enabling organizations to extract insights that may not be possible with structured data.

However, this flexibility comes at a cost; querying unstructured data can be quite challenging. Traditional databases and querying languages (like SQL) are optimized for structured data, which is neatly organized in rows and columns. For unstructured data, specialized tools and techniques (like natural language processing or machine learning algorithms) may be required to effectively analyze and derive meaningful insights from the data, making the querying process inherently more complex. Thus, the assertion that unstructured data is the hardest to query but the most flexible accurately reflects the characteristics of different data types.