Final answer:
At room temperature, 1,3-butadiene reacts with HCl to give the 1,4-Addition product in higher yield due to the stability of the intermediate carbocation formed in this reaction. The option (A) is correct.
Step-by-step explanation:
When HCl is reacted with 1,3-butadiene at room temperature, the product with a higher yield is the 1,4-addition product. This is because, in the presence of a polar protic acid like HCl, 1,3-butadiene typically undergoes conjugate addition (also known as 1,4-addition).
This reaction leads to the formation of a more stable secondary carbocation intermediate which can then react with a chloride ion to give the 1,4-addition product. The 1,2-addition product, which involves the formation of a less stable primary carbocation, is formed as well, but with a lower yield compared to the 1,4-addition product at room temperature. At higher temperatures, the 1,2-addition product could predominate due to kinetic control. Therefore, option (A) is correct.