Correct option is (d) LiAlH4
LiAlH4 is a powerful reducing agent that can reduce carboxylic acids, such as propionic acid, to their corresponding primary alcohols. In this case, it will reduce propionic acid to 1-propanol. The reaction can be represented as follows:
CH3CH2COOH (Propionic acid) + 4LiAlH4 → CH3CH2CH2OH (1-Propanol) + 4LiAlO2 + 4H2