A. Increase the size of the virtual warehouse used for data loading. Use INSERT statements to load directly from the staged files using the JSON data.

B. Create a smaller virtual warehouse specifically for data loading, and a separate, larger warehouse for querying. Use INSERT statements with 'OBJECT_CONSTRUCT to pre-process the JSON data before insertion.

C. Use INSERT with SELECT statements to load the data and utilize the SLATERAL FLATTEN' function during the insertion process to flatten the nested JSON structure into relational columns.
Ensure the virtual warehouse used is appropriately sized and consider clustering the
'PRODUCT_REVIEWS' table based on commonly queried fields after loading.

D. Use INSERT statements to load the data into a staging table with a VARIANT column. After the load, use CREATE TABLE AS SELECT (CTAS) with 'LATERAL FLATTEN' to transform the data into a structured table. Finally, swap the original table with the newly created structured table. Use smallest virtual warehouse.

E. Use INSERT with SELECT statements to load the data and utilize the `LATERAL FLATTEN' function during the insertion process to flatten the nested JSON structure into relational columns.Use 'auto suspend' feature on virtual warehouse to save costs.