The correct answer is option 1: Both A and R are individually true and R is the correct explanation of A.

Assertion (A) states that butter softens at room temperature, which is true. When butter is kept at room temperature, it becomes softer and easier to spread or use in recipes.

Reason (R) states that short chain fatty acids cause the melting point to decrease, which is also true. Butter is primarily made up of fat, and the composition of fats affects their melting points. Short chain fatty acids have lower melting points compared to long chain fatty acids, so when butter contains a higher proportion of short chain fatty acids, it will have a lower melting point and soften at room temperature.

In this case, the reason (R) relates directly to the assertion (A), explaining why butter softens at room temperature. Therefore, option 1 is the correct answer.

Alert - The given answer is correct.