ANS:A - < 1

In a liquid-liquid heat exchanger, the ratio of the Logarithmic Mean Temperature Difference (LMTD) in parallel flow to the LMTD in counter flow can vary depending on the specific conditions of the heat exchanger, such as flow rates, inlet temperatures, and fluid properties. However, it's generally observed that for the same process temperature, the ratio of the LMTD in parallel flow to the LMTD in counter flow is always greater than 1. This is because the LMTD in counter flow is generally greater than the LMTD in parallel flow for liquid-liquid heat exchangers. So, the correct answer is: "> 1"