Assertion:. The word salary comes from the Latin word Salarium which means payment by salt.

Reasoning: In earlier times salt was mode of payment. Producing salt from sea water was unknown and could only be made from rock salt which was rare and expensive.

Both Assertion (A) and reasoning (R) are correct and R is the correct explanation of A.

The correct answer is Option 1: Both Assertion (A) and reasoning (R) are correct and R is the correct explanation of A.

Assertion:. The word salary comes from the Latin word Salarium which means payment by salt. This statement is correct. The word “salary” is historically linked with salt payments or allowances.

Reasoning: In earlier times salt was mode of payment. Producing salt from sea water was unknown and could only be made from rock salt which was rare and expensive. This is also correct. Before modern industrial evaporation pans, salt was structurally difficult to acquire inland. Because it was an essential preservative for food survival and highly scarce, it possessed massive intrinsic economic value—comparable to precious metals.

Does R explains A? Yes. The Reason explains why salt was valuable enough to be used as payment, which in turn explains the origin of the word Salarium. 

NCERT: "The word salary comes from the Latin word Salarium which means payment by salt. As in those times producing salt from sea water was unknown and could only be made from rock salt which was rare and expensive. That is why it became a mode of payment."