The laboratory tests on a soil sample yields the following results: natural moisture content = 18%, liquid limit = 60%, plastic limit = 25%, percentage of clay sized fraction = 25%. The liquidity index and activity (as per the expression proposed by Skempton) of the soil, respectively, are

• A. -0.2 and 1.4
• B. 0.2 and 1.4
• C. -1.2 and 0.714
• D. 1.2 and 0.714