The query will return all rows from both df1 and df2 where the 'id' values match, excluding any rows without a match. This option suggests an inner join, which is not the intended operation here.

The query will return all rows from df1, including those without a matching 'id' in df2, and only the matching rows from df2, with NULL values for non-matching rows in df2. This option correctly describes the left join operation and is optimized for performance by minimizing the data shuffled across the network.

The query will return only the rows from df1 that have a matching 'id' in df2, along with the corresponding rows from df2. This option incorrectly describes the left join as it excludes rows from df1 without a match in df2.

The query will return all rows from df2, including those without a matching 'id' in df1, and only the matching rows from df1, with NULL values for non-matching rows in df1. This option describes a right join, not a left join.

The query will return all rows from df1 and df2, combining them in a way that includes all possible combinations of rows, regardless of 'id' matches. This option describes a cross join, which is not the intended operation here.